Platform abstraction layer for a wireless malware scanning engine

ABSTRACT

A system, method and computer program product are provided for scanning a mobile wireless device for malware. Initially, a platform abstraction layer of a mobile wireless device is called. Further, an anti-malware scanner-related function module on the mobile wireless device is initiated utilizing the platform abstraction layer. Such platform abstraction layer enables the anti-malware scanner-related function module to be initiated on any of a plurality of different mobile wireless devices.

RELATED APPLICATION(S)

The present application is a continuation of an application entitled “SYSTEM, METHOD AND COMPUTER PROGRAM PRODUCT FOR EQUIPPING WIRELESS DEVICES WITH MALWARE SCANNING CAPABILITIES” naming the same inventors and filed Apr. 10, 2002 under Ser. No. 10/121,087 which, in turn, is a continuation-in-part of an application filed Nov. 30, 2001 under Ser. No. 10/006,413 now U.S. Pat. No. 6,792,543 which, in turn, is a continuation-in-part of an application filed Aug. 1, 2001 under Ser. No. 09/920,065, now U.S. Pat. No. 6,718,469 which are each incorporated herein by reference in their entirety.

FIELD OF THE INVENTION

The present invention relates to wireless device security, and more particularly to scanning wireless devices for malware.

BACKGROUND OF THE INVENTION

The last decade has seen a rapid growth in the number and use of mobile cellular telephones. More recently, wireless devices have been introduced which combine the functionality of mobile telephones and Personal Digital Assistants (PDAs). It is expected that this area will undergo massive growth in the near future as new cellular telecommunication standards (e.g. GPRS, UMTS, and WAP) make possible the high speed transfer of data across the wireless interface.

It can be expected that such platforms will be susceptible to attack from so-called “malware” such as viruses, Trojan horses, and worms (referred to collectively hereinafter as “viruses”) in much the same way as present day personal computers and workstations are susceptible to malware attack. A number of mobile telephone viruses have already been identified.

In order to resist virus attacks, anti-virus software must be deployed into mobile platforms in much the same way as it has been deployed in the desktop environment. A number of different desktop anti-virus applications are currently available. The majority of these applications rely upon a basic scanning engine which searches suspect files for the presence of predetermined virus signatures. These signatures are held in a database which must be constantly updated to reflect the most recently identified viruses.

Typically, users download replacement databases every so often, either over the Internet, from a received e-mail, or from a CDROM or floppy disk. Users are also expected to update there software engines every so often in order to take advantage of new virus detection techniques (e.g. which may be required when a new strain of virus is detected).

Mobile wireless platforms present a series of problems for software developers (including developers of anti-virus software). Chief among these are the limited memory and processing power of mobile platforms, and the limited input/output capabilities which they possess (i.e. no CDROM or floppy drive, and no high bandwidth fixed line network or Internet connectivity).

Moreover, mobile wireless platforms are traditionally not standardized like conventional desktops. For example, instead of running Microsoft™ Windows™, such mobile wireless platforms may have installed thereon a variety of types of operating systems.

This complicates the act of designing an anti-virus scanner that is capable of operating on any one of a plurality of mobile wireless platforms.

DISCLOSURE OF THE INVENTION

A system, method and computer program product are provided for scanning a mobile wireless device for malware. Initially, a platform abstraction layer of a mobile wireless device is called. Further, an anti-malware scanner-related function module on the mobile wireless device is initiated utilizing the platform abstraction layer. Such platform abstraction layer enables the anti-malware scanner-related function module to be initiated on any of a plurality of different mobile wireless devices.

In one embodiment, the platform abstraction layer may include storage I/O interfaces. Further, the platform abstraction layer may include dynamic memory allocation interfaces, process control call interfaces, network I/O call interfaces, system event handler interfaces, and/or system information routine interfaces.

In another embodiment, the platform abstraction layer may provide a common view of an operating system of the mobile wireless device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an exemplary architecture for scanning a mobile wireless device for malware, in accordance with one embodiment.

FIG. 2 illustrates an overview of the component architecture associated with the anti-malware scanner running on the mobile wireless devices.

FIG. 3 illustrates a method for scanning a mobile wireless device for malware utilizing a user interface, in accordance with one embodiment.

FIG. 4 illustrates a sample user interface screen that shows the features exposed by the anti-malware scanner.

FIG. 5 illustrates a block diagram showing the interaction between a component manager and other subsystems such as the user interface.

FIG. 6 illustrates a method for scanning a mobile wireless device for malware utilizing a component manager, in accordance with one embodiment.

FIG. 7 illustrates a system including an on-access scanner, in accordance with one embodiment.

FIG. 8 illustrates a framework with an on-access scanner interfacing with a file system, and filtering all file I/O related events.

FIG. 9 illustrates the manner in which the on-access scanner is enabled and disabled during use based on on-demand scanning.

FIG. 10 illustrates a Java scanning module interfacing with Java, and filtering all Java applet and Java script executions.

FIG. 11 illustrates an on-demand scanner system including an on-demand scanner interacting with a component manager and a scan engine.

FIG. 12 illustrates a method for performing on-demand scanning, in accordance with one embodiment.

FIG. 13 illustrates a scan engine system including a scan engine module, a file parser, and an interpreter.

FIG. 14 illustrates a service agent (SA) architecture, in accordance with one embodiment.

FIG. 15 illustrates a method for scanning a mobile wireless device for malware, involving service agents.

FIG. 16 illustrates a sample service agent activation method, in accordance with one embodiment.

FIG. 17 provides a method for client and server package handling.

FIG. 18 illustrates the various steps of a package installation process, in accordance with one embodiment.

FIG. 19 illustrates the components of the platform abstraction layer and the manner in which they interface with a mobile wireless device and operating system thereof.

FIG. 20 illustrates a transaction server command process flow, in accordance with one embodiment.

FIG. 21 illustrates a plurality of personal device database table relationships, in accordance with one embodiment.

FIG. 22 shows an exemplary client information flow, in accordance with one embodiment.

DETAILED DESCRIPTION

FIG. 1 illustrates an exemplary architecture 100 for scanning a mobile wireless device for malware, in accordance with one embodiment. As shown, the architecture 100 includes a mobile wireless device 102. Such mobile wireless device 102 may include, but is not limited to a cellular phone, personal digital assistant (PDA), a palm computer, or any combination thereof. Further, such mobile wireless device 102 may rely on any desired operating system. It should be noted that the vast variety of mobile wireless devices 102 operate different operating systems, unlike traditional desktop and laptop environments which typically run Microsoft™ Windows™ operating systems.

As may soon become apparent, the mobile wireless device 102 is associated with an application service provider and is equipped with an anti-malware scanner for providing active content security service. In the context of the present description, such anti-malware scanner may include any program adapted to scan or detect malware (i.e. virus, Trojan horse, worm and other forms of data or program that may result in an unexpected and/or unwanted outcome).

In use, the application service provider is initiated utilizing the mobile wireless device 102. Next, the anti-malware scanner installed on the mobile wireless device 102 is updated over a wireless network utilizing the application service provider. The mobile wireless device 102 is then scanned utilizing the updated anti-malware scanner.

In communication with the mobile wireless device 102 are server-side systems, or a back-end architecture 104. Such back-end architecture 104 is located at a service-provider site and provides centrally managed provisioning, component updates and usage reporting for serviced mobile wireless devices 102.

As shown in FIG. 1, the back-end architecture 104 may, in one embodiment, include a carrier gateway 106 for communicating with the mobile wireless device 102. A load distributor 108 may be coupled between the carrier gateway 106 and a plurality of hypertext transfer protocol (HTTP) servers 110 which, in turn, are coupled to a plurality of transaction servers 112. Further included is a database 114 coupled between the transaction servers 112 and a configuration/reporting server 116.

In use, the back-end architecture 104 receives device requests, and sends and receives client-specific data to and from the mobile wireless devices 102. The transaction servers 112 make database queries to store and retrieve information to/from the database 114. Client configuration information, usage information and component update packages are stored in the database 114. Configuration and reporting maybe accomplished via Web interfaces 118. More information regarding such back-end architecture 104 will be set forth hereinafter in greater detail.

More information will now be set forth regarding an exemplary design of the mobile wireless devices 102. As wireless devices have limited resources, the anti-malware scanner on the mobile wireless devices 102 may be specifically designed with the following objects set forth in Table 1A in mind.

TABLE 1A Maintain a low memory footprint. Consume as little CPU resources as possible, yet maintain active monitoring for malicious software on the device. Minimize bandwidth requirements to the back-end server. Use the back-end server to minimize the work the device is required to perform. Maximize the flexibility of the scanner to address new threats.

The anti-malware scanner may evolve over time as new computer viruses and other malicious code are discovered.

The anti-malware scanner is designed to protect wireless devices 102 from malicious code. The scope of this protection includes, but is not limited to the following set forth in Table 1B.

TABLE 1B Identify malicious code in persistent data stored on the device. This includes native executables as well as scripting languages embedded in documents. Prevent malicious code from being executed by actively intervening when the data is accessed. Potentially monitor network activity to detect and intervene against external threats on the device. Provide a means for cleaning programs and documents that have been infected by malicious software. Report the necessary information to track active threats on the network of wireless devices.

A glossary of terms that will be used in the present description is set forth in Table 1C.

TABLE 1C Term Description Virus A piece of executable binary or script that replicates by modifying and attaching to programs or executable/automation scripts. Viruses may damage data, cause the computer to crash, display messages, or lie dormant. Trojan Horse A program that either pretends to have, or is described as having, a set of useful or desirable features, but actually contains a damaging payload. Most frequently the usage is shortened to “Trojan”. Trojan Horses are not technically viruses, since they do not replicate. Worm A malware that replicates itself using computer networks, such as via email or IRC (Internet Relay Chat). Malware Virus, Trojan horse, worm and other forms of data or program that result in unexpected and/or unwanted outcome. Storage Disk, flash-memory or other forms of non-volatile memory device. File Single storage object entity such as a program or a data file. Directory A storage index that contains a list of files or sub-directories. Archive File Single file containing multiple files organized by a directory structure. Example: ZIP, CAB, JRE, SIS File Scanning The process used for detecting, identifying and removing malware on a storage. Process Scanning The process used for detecting, identifying and removing malware in execution. Application- Malware scanning process for a particular application. specific Scanning Example: hostile SMS/MMS scanning, Email attachment scanning, hostile Java Applet scanning On-demand Malware scanning process initiated by the user or another application. Usually Scanning involves a complete system-wide scanning, and the process is terminated when scanning is completed. On-access Scanning process triggered by an OS or an application event. The on-access Scanning scanner stays resident in the system. Anti-Malware Scanner Architecture

The anti-malware scanner architecture is based on a collection of components. These components are further analysed to expose properties and interfaces. This design helps isolate defects to specific components as well as providing a framework for porting the design to other devices with different hardware requirements.

FIG. 2 illustrates an overview of the component architecture 200 associated with the anti-malware scanner running on the mobile wireless devices. As shown, a user interface 202 is provided which communicates with a component manager 204. Such component manager 204 is responsible for controlling and managing an on-access scanner module 206, on-demand scanner module 208, Java-scanner module 210, service manager module 212, and activity logging module 214. As shown, the on-access scanner module 206, on-demand scanner module 208, and the Java-scanner module 210 utilize a common scan engine 216.

For reasons that will soon become apparent, the anti-malware scanner component architecture 200 further includes a platform abstraction layer 218 that provides an interface between an operating system 220 of the mobile wireless device and the component manager 204 and the components associated therewith. Each of the foregoing components will be discussed subsequently in greater detail.

User Interface Design (202 of FIG. 2)

FIG. 3 illustrates a method 300 for scanning a mobile wireless device for malware utilizing a user interface, in accordance with one embodiment. Initially, in decision 302, it is determined whether an update command is received from a user utilizing a graphical user interface of a mobile wireless device. As an option, the update command may be received upon the selection of an update icon displayed on the graphical user interface of the mobile wireless device. In operation 304, an anti-malware scanner installed on the mobile wireless device is then updated over a wireless network in response to the update command.

Next, it is determined in decision 306 as to whether a scan command has been received via the selection of a scan icon displayed on the graphical user interface of the mobile wireless device. More information regarding an exemplary interface with such icons will be set forth hereinafter during reference to FIG. 4. The mobile wireless device is then scanned utilizing the updated anti-malware scanner, as indicated in operation 308. Such anti-malware scanner may be conditionally updated based on the update command so as to regulate usage of the wireless network with the mobile wireless device.

As an option, a version number of a last update may be displayed utilizing the graphical user interface of the mobile wireless device. Further, a time of a last update may be displayed utilizing the graphical user interface of the mobile wireless device.

The anti-malware scanner user interface is very effective in design. Configuration settings and updates are handled by the back-end system, relieving the user from any responsibilities. Some basic feedback such as the product name, logo, and version information is provided. The user may check for product updates, and initiate a scan for malicious programs on removable media. The details for these capabilities are provided below.

Manual Virus Scanning

Manually virus scanning of the entire device is performed according to the configuration settings set by the IT administrator. That is, either all files may be scanned or only certain types of files. Also, the IT Administrator specifies how the anti-malware scanner responds to any infected file that is found. Upon scan completion, a report is created that reflects what was scanned and whether any computer viruses were found.

Check for Product Updates

Checking for product updates is made available from the main user interface. When update checking is requested, the anti-malware scanner attempts to update itself using a service agent in a manner that will soon be set forth.

About the Anti-malware Scanner

An ‘About the anti-malware scanner’ dialog box is displayed upon user request. The contents of this dialog box contain the information of Table 1C-1.

TABLE 1C-1 All the necessary anti-malware scanner copyright messages. Scan engine and virus definition file version numbers. Last time the product was updated.

FIG. 4 illustrates a sample user interface screen 400 that shows the features exposed by the anti-malware scanner. The user interface screen 400 may be displayed upon the selection of an anti-malware scanner tab 401 always shown on the user interface screen 400. Of course, other tabs such as a contacts tab 401-A, a mail tab 401-B, a browser tab 401-C, an address book tab 401-D, and a notes tab 401-E may also be provided. As shown in FIG. 4, a scan icon 402, an update icon 404, and an about icon 406 are illustrated upon the selection of the anti-malware scanner tab 401 for allowing a user to carry out the functionality of the anti-malware scanner.

Component Manager Design Specification (204 of FIG. 2)

The component manager inside the anti-malware scanner is the logic layer that instantiates the following subsystems of Table 1D.

TABLE 1D On-access scanning subsystem. On-demand scanning subsystem. Activity logging subsystem. Service agent subsystem.

The component manager contains logic on how to instantiate the different subsystems, how to configure them, and manages when to activate and deactivate subsystems. It drives the entire application and can provide the user interface with feedback on subsystem progress.

The user interface relies on the component manager to initiate actions such as manually scanning for computer viruses and to check for product updates.

FIG. 5 illustrates a block diagram 500 showing the interaction between the component manager 502 and the other subsystems 504 such as the user interface 506. As shown, any number of subsystems 508 may be employed per the desires of the user.

How the Component Manager Works

FIG. 6 illustrates a method 600 for scanning a mobile wireless device for malware utilizing a component manager, in accordance with one embodiment. The component manager is initially instantiated, in operation 602, just like any other core technology component of the present embodiment. As an option, the operation 602 may be executed in response to a scan command received from a user utilizing the user interface of the mobile wireless device.

Next, in operation 604, memory is allocated to store private data information for the component manager. The configuration manager is then used to load in anti-malware scanner scan settings in the private memory just allocated. See operation 606.

Based on the scan settings, the specialized subsystems are initiated. See operation 608. These subsystems may include the on-access scanning, activity logging and/or a service agent function. The on-demand scanning subsystem is only instantiated on a per need basis in order to save system resources. On-demand scanning is only needed when manual device scanning is requested. Based on these initialisation steps, a completion return code is returned to the owner of this subsystem.

The on-access scanning subsystem is initiated so real-time monitoring for viruses begins. When a computer virus is detected, a component manager callback function is called by the on-access scanning subsystem. Within this callback function the component manager determines based on the scan settings how it wishes the on-access scanning subsystem to deal with infected items. The completion status of this event is then passed to the activity logging subsystem for recording purposes.

When manual scanning is requested, it is performed according to the established configuration provided by an IT administrator. Manual scanning involves accessing several files or databases on the device and this same action is what the on-access scanner also monitors. In order to not cause system resources to be spent unnecessarily, the on-access scanning subsystem is disabled for the brief time period that the on-demand scanning is active.

Component Manager API

The component manager exposes all its functionality through an API layer. No platform dependencies are necessarily assumed. All interfaces follow a sandwiched approach where there is an initialisation to obtain an instance handle. Based on this instance handle, the component manager worker functions are available and when the object is not needed anymore the object is destroyed. The number of features that a user interface can request to be performed by the component manager may be limited. All knowledge on how scanning is performed may be contained within the component manager. A user interface can request from the component manager to do the following steps of Table 1E.

TABLE 1E Start an on-demand scan. Start the service agent to check for updates. Find out the version of the scan engine and DAT files. Find out when was updating done the last time.

As the component manager handles different specialized subsystems, all events that are generated may be communicated back to the owner of the component manager handle using a callback function. To some of these events the callback function may return a TRUE Boolean value to indicate an affirmative answer that the core technology in question should proceed with the action that is about to happen, or return a FALSE to indicate that the action should not be performed.

As an example, when the service agent indicates that it is about to check for updates, if the callback function returns FALSE, this action may not happen.

See Table 2A for an exemplary component manager API.

TABLE 2A CMgrCreate( ) Description The CMgrCreate( ) function creates an instance of the component manager. A user interface layer that wraps the core technology should make this call. The handle that is returned by this function call should be passed to all subsequent calls to the component manager. Prototype HCMGR CMgrCreate( // Creates a component manager instance PFNCMGRNOTIFY pfnNotify, // [in] Function to notify. PVOID pUserParam // [in[ Any user defined value. ); Parameters pfnNotify [in] Pointer to a notification function that is called to notify the owner of this object about events that are happening. See the description of CMgrNotify( ) function for more information. pUserParam [in] optionally the owner of this object can specify a user specific pointer size value that should be passed to the callback function. This can be handy to eliminate the need of static variables on platforms where static variables are not allowed. Return Values A handle to a component manager object. If NULL value is returned then this function call failed. To find out the reason why this call failed call the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. If the function succeeds it may be a valid handle that should be freed up using the CMgrDestroy( ) function when it is not needed anymore. See Also CMgrDestroy( ), CMgrActivate( ), CMgrNotify( ) CMgrDestroy( ) Description The CMgrDestroy( ) function destroys a component manager object that was created using CmgrCreate( ). When this call is made all specialized subsystems are terminated and all resources associated with these subsystems are freed up. Prototype int CMgrDestroy( // Destroys component manager instance. HCMGR hCmgr // [in] handle to component manager. ); Parameters hCmgr [in] handle to a component manager to destroy. It must have been created using CMgrCreate( ). Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also CMgrCreate( ), CMgrActivate( ), CMgrNotify( ) CMgrActivate( ) Description The CMgrActivate( ) function starts the specified core technology component. It should be called by the user interface to start certain actions such as a manual scan of the device or to start checking for an update. Prototype int CMgrActivate( // Activates a component. HCMGR hCmgr, // [in] handle to component manager. COMPID CompID // [in] subsystem to activate ); Parameters hCmgr [in] handle to a component manager that was created using CMgrCreate( ). CompID Core component identifier that should be activated. This value can be any of the following values. If some other core component value is given an error is returned. COMPID_ONDEMAND, starts a manual scan of the device. COMPID_SERVAGENT, start to check for a product update. Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also CMgrCreate( ), CMgrDestroy( ), CMgrActivate( ), CmgrNotify( ) CMgrNotify( ) Description The CMgrNotify( ) function must be implemented by the calling application and a pointer to it must be passed during initialisation to CMgrCreate( ). This component manager may notify the caller about different events as they are about to occur so the application can record these events if it has to. The application can also indicate using the return code whether the event that it is being notified about should be allowed or disallowed from happening. Prototype BOOL CMgrNotify( // Notification callback function. PCOMPMGRNOTIFYINFO pNotify // Notification structure. ); Parameters pNotify [in] pointer to a notification structure. This structure hold everything needed to properly notify the owner of this object about the events that are happening within the anti-malware scanner core technology. This structure is defined as: typedef struct tagCOMPMGRNOTIFYINFO { PVOID pUserParam; // User defined value used in CompMgrCreate( ) COMPID CompID; // Component that generates this event. VSCNEVENT hEvent; // Why the notification function was called. COMPMGRVALID Valid; // Fields that are valid to check. HVSCNITEM hItem; // Item that scanner is notifying about. SCNDONEACTION DoneAction; // Status of completion status } COMPMGRNOTIFYINFO, *PCOMPMGRNOTIFYINFO; The structure members should be interpreted by the caller as: pUserParam: The same user defined pointer size value that was given to the core component manager during creation is returned in this field. This is a convenient way for applications to not have to resort to global static data usage since this is not supported on many platforms. CompID: This field indicates the component identification number that is notifying about an event that is about to happen, or about an event that just happened. The possible component identification numbers are as follows: COMPID_ONACCESS, On-access scanning subsystem. COMPID_ODNDEMAND, On-demand scanning subsystem. COMPID_ACTILOG, Activity logging subsystem. COMPID_SERVAGENT, Service agent subsystem. hEvent: This is the event that the CompID subsystem is notifying about. The possible event identifiers for this field are as follows: VSE_CANCELLED The previous request that the component manager notified about was cancelled as requested by the object owner. This is nothing more than a confirmation message indicating that the request was understood. At this point the return code from this function has no meaning and it is ignored. VSE_INFECTED The component manager is indicating that a computer virus or some malicious code was found. The subsystem that found this malicious code is known from the CompID component identification number. If the component that found this malicious code is the on-demand scanner, a return code of TRUE indicates that scanning should continue. A return code of FALSE indicates that scanning should be stopped. If FALSE is returned a confirmation notification message VSE_CANCELLED may be sent to the owner of this object. On the on-access and the on-demand scanning subsystems can generate this event. VSE_COMPLSTATUS This event indicates the completion status of the action that was taken on an infected file. This event can only be generated by the on-access and by the on-demand subsystems. For possible completion status codes please see the DoneAction structure member. If the component that found this malicious code is the on-demand scanner, a return code of TRUE indicates that scanning should continue. A return code of FALSE indicates that scanning should be stopped. If FALSE is returned a confirmation notification message VSE_CANCELLED may be sent to the owner of this object. On the on-access and the on-demand scanning subsystems can generate this event. VSE_SCANNINGITEM This is a notification event that tells the owner of this object that a file is about to be scanned for viruses. The file that is about to be scanned has already been pre-filtered based on the IT Administrator specified scan setting so at this way the user interface has no say about what files are being scanned. The only core components that can generate this event are the on-access and the on-demand scanners. Because the user can choose to cancel a user initiated on-demand scan, the return code may only be respected if this event was generated by the on-demand scanner subsystem. A return code of TRUE indicates that scanning should continue. A return code of FALSE indicates that scanning should be stopped. If FALSE is returned a confirmation notification message VSE_CANCELLED may be sent to the owner of this object. VSE_START This event indicates to the caller that the core technology component identified in the CompID structure member just finished initialising. This is only a notification message so any return code that is returned to the component manager from this event notification may be ignored. VSE_END This event indicates to the caller that the core technology component identified in the CompID structure member just terminated. This is only a notification message so any return code that is returned to the component manager from this event notification may be ignored. Valid: This structure member indicates what other fields below this structure member contains valid values. This structure field should be interpreted as a bit field and the individual bits should be access the standard documented ‘C’ coding guideline way. The named bit fields are as follows: bit_hItem, indicates that the hItem structure member is valid. bit_DoneAction, indicates that the DoneAction structure member is valid. hItem: This is a handle to a anti-malware scanner scan item. Information that is associated with this handle can be accessed using the ScnItem family of functions. DoneAction: This structure member indicates the completion status of an action that was performed on an infected item. The completion status can be one of the following values: SCNDONE_NOACTION, Nothing was done about the infected item. SCNDONE_DENIEDACCESS, Infected item was denied access to. SCNDONE_CLEANED, Infected item was cleaned. SCNDONE_CLEANFAILED, Infected item could not be cleaned. SCNDONE_DELETED, Infected item was deleted. SCNDONE_DELETEFAILED, Infected item could not be deleted. Return Values The Boolean return value depends on the type of event that the owner of this object is being notified with. Please see the description of each event for description on what the appropriate return code should be. See Also CMgrCreate( ), CMgrDestroy( ), CMgrActivate( ) On-Access Scanner Module (206 of FIG. 2)

FIG. 7 illustrates a system 700 including an on-access scanner 702, in accordance with one embodiment. In general, the on-access scanner 702 is governed by operating system hooks 704 which provide document access notification. Further, the on-access scanner 702 interfaces with a scan engine 706 to scan documents. Still yet, the on-access scanner 702 reports scan activity to a component manager 708. More information relating to such operation will now be set forth.

The on-access scanner 702 identifies malware as documents are being access on the device. The on-access scanner 702 may be entirely transparent to the user until malicious code is discovered. Scanning can be performed on all executables and documents. This includes word processor documents or files being downloaded by a web browser. The on-access scanner can be configured to only scan certain types of documents.

The on-access scanner 702 is notified of various events related to accessing documents. It then determines whether the document needs to be scanned. The scan engine 706 is used to detect malicious code. When malicious code is discovered, the on-access scanner 702 notifies the component manager 708. It is then the component manager's responsibility to determine which of the following actions in Table 2B to perform.

TABLE 2B Notify the user that malicious code was discovered. Clean the infected file. Once successfully cleaned, the user may access the file. Delete the infected file. This results in an error message displayed to the user that the file could not be accessed. Optionally ask the user whether the infected items should be cleaned, deleted, or just denying access to it.

On-access file scanning is accomplished by hooking into a file access notification mechanism that resides inside the operating system. For a comprehensive protection it is crucial to be able to hook into all file access events prior to them happening and after they have occurred.

The purpose of hooking into all file access events prior to them happening is so they can be intercepted. The purpose of hooking into all file access events after they have occured is so the file in question can be analyzed prior to control being returned to the operating system. An important part of this notification interception is that an application that is part of this notification chain must have the capability to allow or disallow an event from continuing through the file system notification. Of course nothing can be allowed or disallowed once the event has already happened, such as a close event, but in case an infected file is opened, the hooking application must indicate to the operating system that this event should not traverse further in the file system.

The file system related events that are filtered are as follows.

File Create Event

When a file create event is received it may be because the user has decided to download, beam or install some sort of application. When a create event occurs, the anti-malware scanner keeps track of a reference information that is associated with this event, and matches it up with the corresponding close event. This is done because when a new file is created it does not contain any information that can be analyzed for malicious code. It is important to know that if a “file create” event is the same as a file open event, these two are combined into one.

File Open, Execute Program Event

Prior to opening a file, the anti-malware scanner must make sure that the file is not infected. If the file is not infected, identification information is obtained from it. This way, when the file is closed this same information is compared to determine if any changes were made to the file. If changes were made, the anti-malware scanner resorts to a more resource intensive task to ensure that the file does not contain any malicious code. It is important to note that if application execution is a different event from a regular file open event, file execution should be monitored the same way.

File Close Event

The close event must be monitored for several reasons. As described above, when a file is created, it is scanned after the close operation occurred so the anti-malware scanner can analyze its content for computer viruses.

File Rename Event

This is yet another important part of the protection because a smarter computer virus could try to create a text file that contains malicious executable code and prior to launching it, rename it to an executable file type.

On-access Scanner Subsystem Interaction

The on-access scanner subsystem is made usable with the help of other application subsystems. Each subsystem that on-access scanning interacts with are described below. A reason why this interaction is needed is also explained.

Component Manager

When the on-access scanning subsystem determined that there is something important to notify about such as an error condition or that an infected files was found, it informs the component manager.

Scan Engine

The scan engine is the component that takes a file and analyzes it to see if the file contains any malicious code. The scan engine is invoked prior to an open event happening and after a close event has happened.

Operating System

The on-access scanning subsystem must interact with the underlying operating system that informs of all file related events that take place. The operating system may always inform about the following information in Table 2C.

TABLE 2C The full path and filename of the file that is being handled by the operating system. The function that the operating system is about to perform on the indicated file. Any time a drive is being connected and disconnected.

It is important to know that the file system should allow for re-entrancy so when a file system event is intercepted, the file system hooking function can open any file on any drive and perform I/O operations.

On some operating systems it is not possible for an application to use static or global data. Therefore, it would be required on those platforms that a mechanism is provided where the hooked function can access some previously allocated and initiated data.

An example way of accomplishing this would be to have a file system hook installation function that accepts a pointer to a callback function and a void pointer to application defined data. This application defined data would then be passed with every call to the booking function. An example set of functions that are required to perform comprehensive file system hooking is described in Table 3.

TABLE 3 FsInstallHook( ) Description The FsInstallHook( ) function installs a file system hook. All file I/O related events that occur within the operating system are piped through this function. Prototype int FsInstallHook( PFNFSHOOK pAppCallback, void *pUser, PFNFSHOOK *ppPrevHook ); Parameters pAppCallback [in] application defined callback function that should be called for all file system events. See function definition for FsHookFunc( ) for a detailed description. pUser [in] is a user defined data that is passed to the callback function with every call so it can access its own initialized data. pPrevHook [out] pointer to a pointer to the previous file system hooking function. This is required so file system events can be chained. See function definition for FsHookFunc( ) for a detailed description. Return Values A return value of zero should be returned for success or any other number to indicate an error condition. See Also FsUninstallHook( ), FsHookFunc( ) FsUninstallHook( ) Description The FsUninstallHook( ) function removes a previously installed file system hook. Prototype int FsUninstallHook( PFNFSHOOK pAppCallback ); Parameters pAppCallback [in] application defined file system callback function that was installed. See function definition for FsHookFunc( ) for a detailed description. Return Values A return value of zero should be returned for success or any other number to indicate an error condition. See Also FsInstallHook( ), FsHookFunc( ) FsHookFunc( ) Description The FsHookFunc( ) is an application defined function that the operating system calls before a file event occurs. This allows an application to be notified of all file I/O related events before they occur and the application has the capability of allowing or disallowing a file I/O event from continuing. Because FsHookFunc( ) is called before the event occurs, the hooking function may most likely chain this event to the next caller in the list using the pPrevHook value that was returned during hook installation. In case the hooking function determines that further chaining of this file I/O event should not continue, it may return an error indicating this intent. As noted previously, the file system should allow for reentrancy so within FsHookFunc( ) the application can perform I/O operations on any other file that it chooses. Prototype int FsHookFunc( POSFILESTRUCT pOsFileInfo, void *pUserParam ); Parameters pOsFileInfo [in] this is an operating system dependent structure that contains all the necessary information needed by the operating system to perform a file I/O related function. As an example of information that a hooking function could obtain from here are: Full path and filename to the file being accessed. File system function identifier that is currently being requested such as CREATE, OPEN, EXECUTE, CLOSE, READ, WRITE, Etc. Function specific attributes such as file open attributes for an open function and file handle for a close function. Return Values A return value of zero indicates success and any other number to indicate an error condition. When an error is returned the operating system should not process this event. See Also FsInstallHook( ), FsUninstallHook( ) On-Access Scanner API

To protect against malicious code such as computer viruses, the anti-malware scanner requires access to all files being accessed through system provided APIs. The on-access scanning subsystem resides parallel to the other specialized subsystems and as such the component manager manages it.

FIG. 8 illustrates a framework 800 with an on-access scanner 801 interfacing with the file system 802 and filtering all file I/O related events. Every file that is about to be accessed is passed to the scan engine 804 that determines whether it is safe to access it. If the scan engine 804 determines that it is not safe, the component manager 806 may be notified and, based on established scan settings, some action may be done on the infected file. See Table 4 for an exemplary API.

TABLE 4 OnAccCreate( ) Description The OnAccCreate( ) function creates an instance of the on-access scanning subsystem. If the creation returns success the subsystem is ready to monitor for viruses in real-time. The actual monitoring may begin when the OnAccEnable( ) function is called to request the subsystem to enable itself. Prototype HONACCESS OnAccCreate( // Creates on-access scan instance PFONACCNOTIFY pfnNotify, // [in] Function to notify. PVOID pUserParam // [in[ Any user defined value. ); Parameters phOnAccess [out] pointer to an on-access scanner handle. This is the same handle that must be passed to OnAccDestroy( ) before the application terminates. pfnNotify Address to a notification function. If NULL is passed in, all notifications may be turned off. Please see OnAccNotify( ) function for a detailed description of this function. pUserParam A user defined value that may be passed to the call-back function. Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also OnAccDestroy( ), OnAccEnable( ), OnAccNotify( ) OnAccDestroy( ) Description The OnAccDestroy( ) function destroys an on-access scan instance that was created using OnAccCreate( ). There is no need to call OnAccEnable( ) function to disable the on-access scanning subsystem prior to destroying. Prototype int OnAccDestroy( // Destroys on-access scan instance. HONACCESS hOnAccess // [in] handle to destroy ); Parameters hOnAccess [in] handle to an on-access scanner subsystem. This is the same handle that was created using OnAccCreate( ). Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also OnAccCreate( ), OnAccEnable( ), OnAccNotify( ) OnAccEnable( ) Description The OnAccEnable( ) function allows the caller to enable and disable the on-access scanning subsystem that was created using OnAccCreate( ). The on-access scanner is enabled and disabled internally to the anti-malware scanner when an on-demand scan is started. This is done so the on- access scanner does not interfere with the on-demand scanners work. When on-demand scanning is completed, on-access scanning is re-enabled. Prototype int OnAccEnable( // Enable on-access scan subsystem. HONACCESS hOnAccess, // [in] handle to on-access scanner. BOOL bEnable // [in] TRUE/FALSE to enable/disable. ); Parameters hOnAccess [in] handle to an on-access scanner subsystem. This is the same handle that was created using OnAccCreate( ). bEnable [in] A Boolean TRUE to indicate that the on-access scanning subsystem should be enabled, that is it should monitor for file activities and scan files as they are being accessed. A Boolean value of FALSE disables the on-access scanning subsystem. Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also OnAccCreate( ), OnAccDestroy( ), OnAccNotify( )

Table 5 illustrates additional optional components of the on-access scanner API.

TABLE 5 OnAccNotify( ) Description The OnAccNotify( ) function is only a placeholder and it should be defined by the calling application in case the application would like to be notified of events that are occurring within the on-access scanning subsystem. A pointer to this function should be passed to OnAccCreate( ). Prototype typedef BOOL (*PFONACCNOTIFY)(PONACCNOTIFYINFO pNotify); Parameters pNotify [in] pointer to a notification structure that contains all the relevant information regarding the reason that the notification function was called. Important to know that during on-access scanning subsystem initialization the caller indicates what events it would like to be notified on. This structure is defined as follows: // ------------------------------------------------------------- ----------- // Structure used by the on-access scanning subsystem to notify parent. // ------------------------------------------------------------- ----------- typedef struct tagONACCNOTIFYINFO { UInt16 uThisSize; // Size of this structure. PVOID pUserParam; // User defined value used in OnAccCreate ( ) VSCNEVENT hEvent; // Reason why the notification was called. HVSCNITEM hItem; // Item that scanner is notifying about. VSWSCNACTION ScnAction; // Set if hEvent = = VSE_INFECTED SCNDONEACTION DoneAction; // Set if hEvent = = VSE_COMPLSTATUS } ONACCNOTIFYINFO, *PONACCNOTIFYINFO; uThisSize This is a 16-bit unsigned integer value indicating the size of this structure. This information is very useful to know for debugging purposes to ensure proper structure packing. pUserParam This is the same pointer size user defined value that was passed to the subsystem during initialization. This is a convenient way for applications to associate data with an object without the need of using global variables and such. hEvent This is an event identifier that specifies the reason why the callback function was called. The possible event identifiers for this field are as follows: VSE_CANCELLED The previous request that the component manager notified about was cancelled as requested by the object owner. This is nothing more than a confirmation message indicating that the request was understood. At this point the return code from this function has no meaning and it is ignored. VSE_INFECTED The component manager is indicating that a computer virus or some malicious code was found. The subsystem that found this malicious code is known from the CompID component identification number. If the component that found this malicious code is the on-demand scanner, a return code of TRUE indicates that scanning should continue. A return code of FALSE indicates that scanning should be stopped. If FALSE is returned a confirmation notification message VSE_CANCELLED may be sent to the owner of this object. On the on-access and the on-demand scanning subsystems can generate this event. VSE_COMPLSTATUS This event indicates the completion status of the action that was taken on an infected file. This event can only be generated by the on-access and by the on-demand subsystems. For possible completion status codes please see the DoneAction structure member. If the component that found this malicious code is the on-demand scanner, a return code of TRUE indicates that scanning should continue. A return code of FALSE indicates that scanning should be stopped. If FALSE is returned a confirmation notification message VSE_CANCELLED may be sent to the owner of this object. On the on-access and the on-demand scanning subsystems can generate this event. VSE_SCANNINGITEM This is a notification event that tells the owner of this object that a file is about to be scanned for viruses. The file that is about to be scanned has already been pre-filtered based on the IT Administrator specified scan setting so at this way the user interface has no say about what files are being scanned. The only core components that can generate this event are the on-access and the on-demand scanners. Because the user can choose to cancel a user initiated on-demand scan, the return code may only be respected if this event was generated by the on-demand scanner subsystem. A return code of TRUE indicates that scanning should continue. A return code of FALSE indicates that scanning should be stopped. If FALSE is returned a confirmation notification message VSE_CANCELLED may be sent to the owner of this object. VSE_START This event indicates to the caller that the core technology component identified in the CompID structure member just finished initializing. This is only a notification message so any return code that is returned to the component manager from this event notification may be ignored. VSE_END This event indicates to the caller that the core technology component identified in the CompID structure member just terminated. This is only a notification message so any return code that is returned to the component manager from this event notification may be ignored. hItem: This is a handle to a scan item. Information that is associated with this handle can be accessed using the ScnItem family of functions. DoneAction: This structure member indicates the completion status of an action that was performed on an infected item. The completion status can be one of the following values: SCNDONE_NOACTION, Nothing was done about the infected item. SCNDONE_DENIEDACCESS, Infected item was denied access to. SCNDONE_CLEANED, Infected item was cleaned. SCNDONE_CLEANFAILED, Infected item could not be cleaned. SCNDONE_DELETED, Infected item was deleted. SCNDONE_DELETEFAILED, Infected item could not be deleted. Return Values The Boolean return value depends on the type of event that the owner of this object is being notified with. Please see the description of each event for description on what the appropriate return code should be. See Also OnAccCreate( ), OnAccDestroy( ), OnAccEnable( ) ScnItemCreate( ) Description The ScnItemCreate( ) function is used to create an object that contains all information that there is to know about a scan object that is scanned by the on-access scanning subsystem. As an example a ‘Scan Item’ object could contain the name of the file, the virus it was infected with, what type of scan actions the anti-malware scanner attempted to perform on it and the outcome of this operation. Prototype HVSCNITEM ScnItemCreate( void ); // Creates a scan item Parameters None Return Values If NULL value is returned then this function call failed. To find out the reason why this call failed call the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. If the function succeeds it may be a valid handle that should be freed up using the ScnItemDestroy( ) function when it is not needed anymore. See Also ScnItemDestroy( ), ScnItemCopy( ), ScnItemGetItemName( ), ScnItemGetVirusName( ), ScnItemGetActions( ), ScnItemSetAction( ), ScnItemSetUserParam( ), ScnItemGetUserParam( ) ScnItemDestroy( ) Description The ScnItemDestroy( ) function is used to free up all resources associated with a scan item object that was created using ScnItemCreate( ). Prototype int ScnItemDestroy( // Destroys a scan item object. HVSCNITEM hItem // [in] handle to scan item ); Parameters hItem [in] handle to a scan item object that should be destroyed. Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also ScnItemCreate( ), ScnItemCopy( ), ScnItemGetItemName( ), ScnItemGetVirusName( ), ScnItemGetActions( ), ScnItemSetAction( ), ScnItemSetUserParam( ), ScnItemGetUserParam( ) ScnItemCopy( ) Description The ScnItemCopy( ) function is used to create a copy of a scan item object. The copied object may be a carbon copy of the source. Before calling this function make sure to call ScnItemCreate( ) function on the hItemTgt scan item object. Prototype int ScnItemCopy( // Creates a copy of a scan item object. HVSCNITEM hItemSource, // [in] handle to copy HVSCNITEM hItemTarget // [out] a new copy of the item. ); Parameters hItemSource [in] handle to a scan item object that should be copied. hItemTarget [out] handle where the copy may be placed. Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also ScnItemCreate( ), ScnItemDestroy( ), ScnItemGetItemName( ), ScnItemGetVirusName( ), ScnItemGetActions( ), ScnItemSetAction( ), ScnItemSetUserParam( ), ScnItemGetUserParam( ) ScnItemGetName( ) Description The ScnItemGetName( ) function is used to retrieve the name of the item that this object is referencing to. Prototype int ScnItemGetName( // Returns the name of the file. HVSCNITEM hItem, // [in] handle of the scan item. text_t* pBuffer, // [out] file name is placed here. size_t uSize // [in] buffer size in CHARACTERS! ); Parameters hItem [in] handle to a scan item object that is being referenced. pBuffer [out] buffer where the name should be placed. uSize [in] maximum number of characters that can be placed in this buffer. Note that this is not the same as the buffer size! Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also ScnItemCreate( ), ScnItemDestroy( ), ScnItemSetItemName( ), ScnItemGetVirusName( ), ScnItemGetActions( ), ScnItemSetAction( ), ScnItemSetUserParam( ), ScnItemGetUserParam( ) ScnItemSetName( ) Description The ScnItemSetName( ) function is used to set the name of the item that this object is referencing to. Prototype int ScnItemSetName( // Sets the name of the file. HVSCNITEM hItem, // [in] handle of the scan item. text_t* pszItem // [in] file name is placed here. ); Parameters hItem [in] handle to a scan item object that is being referenced. pszItem [in] pointer to a NULL terminated string of characters. Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also ScnItemCreate( ), ScnItemDestroy( ), ScnItemGetItemName( ), ScnItemGetVirusName( ), ScnItemGetActions( ), ScnItemSetAction( ), ScnItemSetUserParam( ), ScnItemGetUserParam( ) ScnItemGetVirusName( ) Description The ScnItemGetVirusName( ) function is used to get the name of the virus that this object is referencing to. Prototype int ScnItemGetVirusName( // Returns the virus name from scan item HVSCNITEM hItem, // [in] handle of the scan item. text_t* pBuffer, // [out] file name is placed here. size_t uSize // [in] buffer size in CHARACTERS! ); Parameters hItem [in] handle to a scan item object that is being referenced. pBuffer [out] buffer where the name should be placed. uSize [in] maximum number of characters that can be placed in this buffer. Note that this is not the same as the buffer size! Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also ScnItemCreate( ), ScnItemDestroy( ), ScnItemGetItemName( ), ScnItemSetVirusName( ), ScnItemGetActions( ), ScnItemSetAction( ), ScnItemSetUserParam( ), ScnItemGetUserParam( ) ScnItemSetVirusName( ) Description The ScnItemSetVirusName( ) function is used to set the name of the virus that this object is referencing to. Prototype int ScnItemSetVirusName( // Sets the name of the virus. HVSCNITEM hItem, // [in] handle of the scan item. text_t* pszItem // [in] file name is placed here. ); Parameters hItem [in] handle to a scan item object that is being referenced. pszItem [in] pointer to a NULL terminated string of characters. Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also ScnItemCreate( ), ScnItemDestroy( ), ScnItemGetItemName( ), ScnItemGetVirusName( ), ScnItemGetActions( ), ScnItemSetAction( ), ScnItemSetUserParam( ), ScnItemGetUserParam( ) ScnItemSetAction( ) Description The ScnItemSetAction( ) function is used to indicate what was done on this scan item by a subsystem such as the scan engine. As an example if cleaning this scan item was attempted, the outcome of this operation should be indicated so other subsystems, such as activity logging can retrieve this information. A queue of the 3 last scan actions is maintained within the object. Prototype int ScnItemSetAction( // Sets a scan action performed. HVSCNITEM hItem, // [in] item that was scanned. SCNDONEACTION Action // [in] scan action performed. ); Parameters hItem [in] handle to a scan item object that is being referenced. Action [in] an identifier that specifies what actions were performed on this object. Possible values for this field are: SCNDONE_NOACTION, Nothing was done about the infected item. SCNDONE_DENIEDACCESS, Infected item was denied access to. SCNDONE_CLEANED, Infected item was cleaned. SCNDONE_CLEANFAILED, Infected item could not be cleaned. SCNDONE_DELETED, Infected item was deleted. SCNDONE_DELETEFAILED, Infected item could not be deleted. Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also ScnItemCreate( ), ScnItemDestroy( ), ScnItemGetItemName( ), ScnItemGetVirusName( ), ScnItemSetVirusName( ), ScnItemGetActions( ), ScnItemSetAction( ), ScnItemSetUserParam( ), ScnItemGetUserParam( ) ScnItemGetActions( ) Description The ScnItemGetActions( ) function is used to retrieve what actions were done on this scan item by subsystems such as the scan engine. A list of the 3 last scan actions is maintained within the scan item object. When the last item is of type OAS_NOACTION, that means no more actions are associated with this scan item. Prototype int ScnItemGetActions( // Returns scan actions performed. HVSCNITEM hItem, // [in] item that was scanned. SCNDONEACTION Action[3] // [out] maximum 3 scan actions. ); Parameters hItem [in] handle to a scan item object that is being referenced. Action[3] [out] an array of identifier that specifies what actions were performed on this object. Possible values for this field are: SCNDONE_NOACTION, Nothing was done about the infected item. SCNDONE_DENIEDACCESS, Infected item was denied access to. SCNDONE_CLEANED, Infected item was cleaned. SCNDONE_CLEANFAILED, Infected item could not be cleaned. SCNDONE_DELETED, Infected item was deleted. SCNDONE_DELETEFAILED, Infected item could not be deleted. Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also ScnItemCreate( ), ScnItemDestroy( ), ScnItemGetItemName( ), ScnItemGetVirusName( ), ScnItemSetVirusName( ), ScnItemGetActions( ), ScnItemSetAction( ), ScnItemSetUserParam( ), ScnItemGetUserParam( ) ScnItemSetUserParam( ) Description The ScnItemSetUserParam( ) function is used to associate any pointer size argument with a scan item object. The meaning of this value is up to the application to define. Prototype int ScnItemSetUserParam( // Associate user defined values. HVSCNITEM hItem, // [in] scan item to associate with. PVOID pUserParam // [in] value to associate. ); Parameters hItem [in] handle to a scan item object that is being referenced. pUserParam [in] Application defined value to associate with this object. Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also ScnItemCreate( ), ScnItemDestroy( ), ScnItemGetItemName( ), ScnItemGetVirusName( ), ScnItemSetVirusName( ), ScnItemGetActions( ), ScnItemSetAction( ), ScnItemSetUserParam( ), ScnItemGetUserParam( ) ScnItemGetUserParam( ) Description The ScnItemGetUserParam( ) function is used to retrieve any application associated value with this object. Prototype int ScnItemGetUserParam( // retrieve associated values. HVSCNITEM hItem, // [in] scan item to associate with. PVOID *ppUserParam // [out] pointer to associated item. ); Parameters hItem [in] handle to a scan item object that is being referenced. ppUserParam [out] Application defined value that was associated with this object. Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also ScnItemCreate( ), ScnItemDestroy( ), ScnItemGetItemName( ), ScnItemGetVirusName( ), ScnItemSetVirusName( ), ScnItemGetActions( ), ScnItemSetAction( ), ScnItemSetUserParam( ), ScnItemGetUserParam( )

FIG. 9 illustrates the manner 900 in which the on-access scanner is enabled and disabled during use based on on-demand scanning. Upon on-demand scanning being requested in operation 902, on-access scanning is disabled in operation 904. Thus, on-demand scanning may be performed in operation 906.

Once the on-demand scanning is complete, the on-access scanning may be enabled in operation 908. By this design, the on-access scanning is disabled when on-demand scanning to preserve resources on the mobile wireless device. In the context of the foregoing interface, the OnAccEnable( ) command may be used to effect the enabling and disabling of the on-access scanning. More information on the on-demand scanning will be set forth hereinafter in greater detail.

Java Scanner (210 of FIG. 2)

Java Applet and Script Scanning

To protect against malicious Java applets and Java scripts, the anti-malware scanner requires access to executable images and scripts through system provided APIs. The Java applet/script scanning subsystem resides parallel to on-access scanning and on-demand scanning subsystems and, as such, it is managed by the component manager.

FIG. 10 illustrates the Java scanning module 1000 interfacing with the Java VM 1002 and filtering all Java applet and Java script executions. Every Java object that is about to be executed is passed to the scan engine 1004 that determines whether it is safe to execute the Java object. If the scan engine determines that it is not safe, the component manager 1006 may be notified and, based on established scan settings, some action may be done on it.

See Table 6 for an exemplary Java Scanner API.

TABLE 6 JavaInstallHook( ) Description The JavaInstallHook( ) function installs a Java applet interpreter or a Java script interpreter hook. All I/O related events that occur within the Java interpreter are piped through this function. Prototype int JavaInstallHook( PFNJAVAHOOK pAppCallback, void *pUser, PFNJAVAHOOK *ppPrevHook ); Parameters pAppCallback [in] application defined callback function that should be called for all Java events. See function definition for JavaHookFunc( ) for a detailed description. pUser [in] is a user defined data that is passed to the callback function so it can access its own initialized data. pPrevHook [out] pointer to a pointer to the previous Java interpreter hooking function. This is required so Java events can be chained. See function definition for JavaHookFunc( ) for a detailed description. Return Values A return value of zero should be returned for success or any other number to indicate an error condition. See Also JavaUninstallHook( ), JavaHookFunc( ) JavaUninstallHook( ) Description The JavaUninstallHook( ) function removes a previously installed Java interpreter hook. Prototype int JavaUninstallHook( PFNJAVAHOOK pAppCallback ); Parameters pAppCallback [in] application defined Java interpreter callback function that was installed. See function definition for JavaHookFunc( ) for a detailed description. Return Values A return value of zero should be returned for success or any other number to indicate an error condition. See Also JavaInstallHook( ), JavaHookFunc( ) JavaHookFunc( ) Description The JavaHookFunc( ) is an application defined function that the Java interpreter calls before a Java applet or a Java script is executed. This allows an application to analyze and allow or disallow the execution of the Java script. Because JavaHookFunc( ) is called before the execution occurs, the hooking function may most likely chain this event to the next caller in the list using the pPrevHook value that was returned during hook installation. In case the hooking function determines that further chaining of this event should not continue, it may return an error indicating this intent. Prototype int JavaHookFunc( PJAVAINTINFO pInterpreterInfo, void *pUserParam ); Parameters [in] pInterpreterInfo This is a Java interpreter dependent structure that contains all the necessary information needed by the Java interpreter to perform I/O related function. As an example of information that a hooking function could obtain from here are: Name of the Java object about to be accessed. Java interpreter specific function identifier that is being performed such as EXECUTE, CLOSE, Etc. Any Java interpreter data that is required to complete the request. As an example for an execute event there should be a buffer pointer to the Java applet or Java script that is about to be executed. [in] pUserParam This is the user defined value that was passed to JavaInstallHook( ) function. It is provided to this function with every call. Return Values A return value of zero indicates success and any other number to indicate an error condition. When an error is returned the Java interpreter should not process this event. See Also JavaInstallHook( ), JavaUninstallHook( ) On-Demand Scanner Module (208 of FIG. 2)

FIG. 11 illustrates an on-demand scanner system 1100 including an on-demand scanner 1101 interacting with a component manager 1102 and a scan engine 1004. Further provided is plug-in support 1006 which interfaces a plurality of abstract file system plug-ins 1108.

The on-demand scanner 1101 is a component of the anti-malware scanner system responsible for scanning collections of data objects. The component manager 1102 initiates calls to the on-demand scanner 1101. The on-demand scanner 1101 makes use of the scan engine 1102 to detect and clean malware. It also makes use of plug-ins 1106, 1108 to determine if a given file can be interpreted as a directory. For example, a compress archive can be enumerated like a directory. The plug-ins 1108 may supply alternate translations to files for decompression, decryption, or other aspects of using the file.

The on-demand scanner 1101 recursively enumerates all data objects on the device from a given starting location. While scanning files, three callback functions are used: pScanFile, pScanDirectory, and pCleanFile. To use the on-demand scanner 1101, the caller must initialise an SE_SCANNER from the scan engine 1104 and the proper callback functions.

FIG. 12 illustrates a method 1200 for performing on-demand scanning, in accordance with one embodiment. As shown, the scanner is started in operation 1202, after which a first entry is identified in operation 1204. It is then determined whether the entry is of a file type or a directory type in decision 1206.

If the entry is of a file type, a filter is obtained in operation 1208, after which a file callback is executed in operation 1210. Based on the callback function, the file is then conditionally scanned in operation 1212. If the file is deemed infected, a clean callback is executed. See operation 1214.

If, on the other hand, the entry is of a directory type (see decision 1206), a directory callback is executed in operation 1216. Next, a recursive scan is executed in operation 1218. The foregoing method 1200 is continued until all of the entries are identified (see operation 1220).

On-Demand Scanner API

An exemplary API for carrying out the foregoing functionality is set forth in Table 7.

TABLE 7 SCAN_ACTION Description The SCAN_ACTION enumeration is used by callback functions to tell the on-demand scanner what to do when the callback function returns. CONTINUE_RECURSIVE_SCAN Continue scanning. This is the most common return value for callback functions. ABORT_RECURSIVE_SCAN Aborts the on-demand scanner immediately. NEXT_RECURSIVE_SCAN Skip the next item to be scanned. This may be used to skip files or directories depending on the callback function that returns this value. Prototype typedef enum { CONTINUE_RECURSIVE_SCAN, ABORT_RECURSIVE_SCAN, NEXT_RECURSIVE_SCAN } SCAN_ACTION; ODCreateScanner Description Create an on-demand scanner. Prototype HODS ODCreateScanner(HVSOPTS hOpts) Parameters hOpts [in] This is a handle to the configuration options. Return Value The returned handle is used for setting callback functions and launching the recursive scan. It must be destroyed when no longer needed with ODDestroyScanner. See Also ODDestroyScanner( ), ODSetFileCallback( ), ODSetDirCallback( ), ODSetCleanFileCallback( ). ODDestroyScanner Description Destroys the given scanner. This must be called once the scanner is no longer needed. Prototype int ODDestroyScanner(HODS hScanner) Parameters hScanner [in] The scanner to destroy. All resources allocated for the scanner are released. Return Value Returns 0 on success, otherwise −1 on error. See Also ODCreateScanner( ) ODSetScanFileCallback Description The pScanFileCallback ( ) is called by the ODScanRecursiveDir( ) function just before each file is scanned. The data pointer sent to ODSetScanFileCallback ( ) is passed to the pScanFileCallback( ). This enables the application to supply context information. Prototype void ODSetScanFileCallback ( HODS *pScan, PSCANFILECALLBACK pScanFileCallback, void *pData ); Parameters pScan [in] This is a pointer to the scan engine that may be used with the ODScanRecursiveDir( ). pScanFileCallback [in] This is the callback function to be used by ODScanRecursiveDir( ). pData [in] This is a pointer to any data that is needed by pScanFileCallback. See Also ScanFileCallback( ), ODScanRecursiveDir( ). ScanFileCallback Description This function is implemented by the ODScanRecursiveDir( ) caller. It is used by ODScanRecursiveDir( ) to notify the caller when a file is about to be scanned, and provides an opportunity to direct the scanner's behaviour. Prototype typedef SCAN_ACTION (*PSCANFILECALLBACK)( void *pData, FILEPATH *pFName ); Parameters pData [in] This is the pointer that was supplied to ODSetScanFileCallback( ). It can be used for whatever the callback function requires. pFName [in] The full path and file name is supplied in pFName. Return Values ScanFileCallback( ) must return one of the following: CONTINUE_RECURSIVE_SCAN. This is the normal return value so that the file may be scanned. ABORT_RECURSIVE_SCAN. This is used to stop scanning entirely. The given file is not scanned. NEXT_RECURSIVE_SCAN. The given file is not scanned. The recursive scan continues with the next file. It is recommended that care be taken not to use much stack space in the callback function. Some platforms have very limited stack space, and the recursive scan requires a fair amount. Be aware that calls into system GUI functions may cause a stack overflow. One successful technique for handling this problem is to setup a timer. The callback function merely copies information for the timer to consume. The timer event displays progress and interacts with the user using a separate stack. ODSetDirCallback Description The ScanDirCallback ( ) is nearly identical to the ScanFileCallback ( ) except for one detail. Instead of reporting files, it reports directories before scanning them. Prototype void ODSetScanDirCallback ( HODS hScan, PSCANDIRCALLBACK *pScanDirCallback, void *pData ); Parameters pScan [in] This is a pointer to the scan engine that may be used with the ODScanRecursiveDir( ). pScanDirCallback [in] This is the directory callback function to be used by ODScanRecursiveDir( ). PData [in] This is a pointer to any data that is needed by pScanDirCallback. See Also ODScanRecursiveDir( ), ScanDirCallback( ), ScanFileCallback( ), ODSetScanFileCallback( ). ScanDirCallback Description This function is implemented by the ODScanRecursiveDir( ) caller. It is used by ODScanRecursiveDir( ) to notify the caller when a directory is about to be scanned, and provides an opportunity to direct the scanner's behavior. Prototype typedef SCAN_ACTION (*PSCANDIRCALLBACK)( void *pData, DIRPATH *pFName ); Parameters pData [in] This is the pointer that was supplied to ODSetScanDirCallback( ). It can be used for whatever the callback function requires. pFName [in] The full path is supplied in pFName. Return Values The return values are the same as pScanFileCallback( ). See Also pScanFileCallback( ), ODScanRecursiveDir( ), ODSetScanDirCallback( ), ODSetScanFileCallback( ) ODSetCleanFileCallback Description The pCleanFileCallback ( ) is called when malware is discovered by the ODScanRecursiveDir ( ) function. All the information necessary to call SECleanFile ( ) is supplied. It is up the to the callback function to call SECleanFile ( ) if needed. As scanner state information is needed by the SECleanFile ( ) function, it must be called before continuing the recursive scan, or not at all. Storing the scan_result_t id, and calling SECleanFile ( ) after returning from the callback may have unexpected results. Prototype void ODSetCleanFileCallback ( HODS hScan, PCLEANFILECALLBACK pCleanFileCallback, void *pData ); Parameters pScan [in] This is a pointer to the scan engine that may be used with the ODScanRecursiveDir( ). pCleanFileCallback [in] This is the callback function to be used by ODScanRecursiveDir( ). pData [in] This is a pointer to any data that is needed by pCleanFileCallback. See Also ODScanRecursiveDir( ), CleanFileCallback( ), SECleanFile( ). CleanFileCallback Description The CleanFileCallback ( ) called when an infected file is discovered. The callback function is responsible for deciding what must be done with the malware, and executes the response. The response may be a call to SECleanFile( ). Prototype typedef SCAN_ACTION (*PCLEANFILECALLBACK)( Void *pData, HODS hScan, FILEPATH *pFileName, scan_result_t id ); Parameters pData [in] A pointer to the pData sent to ODSetCleanFileCallback( ). pScan [in] A pointer to the SCANNER that was used to detect the infected file. pEnt [in] A pointer to the directory entry of the file that is infected. pFile [in] A pointer to the file opened that is infected. The file is opened for read/write access. id [in] This is the ID of the malware discovered. This can be used with SEScanGetName( ) and SEScanGetVariant( ) to retrieve the name. Return Values The CleanFileCallback( ) may return CONTINUE_RECURSIVE_SCAN or ABORT_RECURSIVE_SCAN. See Also ODScanRecursiveDir( ), pScanDirCallback( ), pScanFileCallback( ), ODSetScanFileCallback( ). ODScanRecursiveDir Description Scan all the files in the given pADir, as well as recurs into subdirectories. This is used for on- demand scanning. Feedback is provided during the recursive scan through three callback functions: ODScanFileCallback, ODScanDirCallback, and ODCleanFileCallback. The ODScanFileCallback ( ) is called just before the given file is scanned. This provides the calling application an opportunity to track scan progress, to skip files, and abort scanning. The ODScanDirCallback ( ) is called just before the given directory is scanned. Just like the ODScanFileCallback( ), the application can track progress, skip the directory, or abort scanning. The ODCleanFileCallback ( ) is only used when malware is detected. The application then needs to choose the proper action. This may include calling the SECleanFile ( ) function. Any callback not set, or set to NULL, is ignored. Prototype SCAN_ACTION ODScanRecursiveDir(HODS hScan, HDIR hDir); Parameters pScan [in] This is a pointer to the SCANNER to use. Call SEScanOpen( ) to create a new SCANNER. The caller is responsible to calling SEScanClose( ) once the ODScanRecursiveDir( ) is done. pADir [in] This is a pointer to the root directory to start the recursive scan. Return Values The SCAN_ACTION returned denotes how the function ended: CONTINUE_RECURSIVE_SCAN or ABORT_RECURSIVE_SCAN. A return value of CONTINUE_RECURSIVE_SCAN indicates that it successfully completed the scan. ABORT_RECURSIVE_SCAN indicates that the scan was aborted. Plug-in API The on-demand scanner supports adding plug-ins for new abstract directory and file types. This enables adding support for compressed archives and other special file formats. ODRegisterDirFilter Description The caller supplies a callback function for creating HDIR instances. The callback function takes an HFILE and detects whether the HFILE can be interpreted as an ADIR. The callback function must return an HDIR or NULL. Prototype void ODRegisterDirFilter( PDIRFILTERCALLBACK pDirFilterCallback ); Parameters pDirFilter [in] This is a pointer to a callback function to create the HDIR based on an HFILE. See Also DirFilterCallback( ) DirFilterCallback Description This callback function is responsible for determining whether the given pAFile can be represented as an ADIR. For example, compressed archives may be treated as an ADIR so that the contents can be enumerated and scanned. Prototype HDIR DirFilterCallback( HFILE hFile ); Parameters hFile [in] A valid HFILE opened for reading. Return Values The callback must return NULL if it is not able to use the provided hFile. Otherwise, it returns a valid HDIR implementation for the pAFile. The callback can rely in the hFile to continue to be open for the life of the returned HDIR. See Also ODRegisterADirCallback( ) ODRegisterFileFilter Description The caller supplies a callback function for creating AFILE instances. The callback function takes an hFile and detects whether it is supported. If supported, the callback function returns a new HFILE. Otherwise, NULL. Prototype void ODRegisterFileFilter( PFILEFILTERCALLBACK pFileFilterCallback ); Parameters pFileFilterCallback [in] The callback function to create an HFILE filter. See Also FileFilterCallback( ) FileFilterCallback Description This callback function is used to determine if this filter supports the given hFile. If the hFile is supported, this function creates an HFILE interface to wrap the hFile. Prototype HFILE (*PFILEFILTERCALLBACK)(HFILE hFile) Parameters hFile [in] Provided is an HFILE opened for reading. It may remain open for the duration of the returned HFILE from this function. Return Value Returns NULL if the given hFile is not supported. Otherwise, it creates an HFILE interface, and returns that. See Also ODRegisterFileFilter( ) ODOpenDirFilter Description Looks for an HDIR interface for the given HFILE. Prototype HDIR *ODOpenDirFilter(HFILE hFile); Parameters hFile [in] An HFILE opened for reading. Return Values Returns an HDIR. The hFile must remain available for the returned HDIR to use in accessing the file. The caller is responsible for releasing both the HDIR and hFile. Note that the caller must not release the hFile until after releasing the returned HDIR. Returns NULL if no HDIR filter is available. ODOpenFileFilter Description Looks for an alternate HFILE interface for the given HFILE. Prototype HFILE ODOpenAFileFilter(HFILE hFile, AFILE_MODE mode); Parameters hFile [in] The HFILE to use with the filter. mode [in] This is the read/write mode to use when the file is created. This should be compatible with the hFile's mode. Return Values The supplied hFile must remain available for the returned HFILE to access. The caller is responsible for releasing both the returned HFILE and supplied hFile. Note that the caller must not release the hFile until after releasing the returned HFILE. Returns NULL if no HFILE filter is available. Scan Engine (216 of FIG. 2)

FIG. 13 illustrates a scan engine system 1300 including a scan engine module 1302, a file parser 1304, and an interpreter 1306. The scan engine system 1300 interfaces the on-access and on-demand scanner modules 1308 to carry out virus detection and clean files. See operation 1310.

The scan engine system 1300 is responsible for scanning individual data objects for malware and to repair infected documents. Potentially infected data is presented to the scan engine system 1300 from the on-access and on-demand scanner modules 1308. It is built to be system independent, and thus has an abstraction for data objects that can be scanned and cleaned.

Scan Engine API

The purpose of the scanner API is to enable the on-demand and on-access scanner modules 1308 to initiate detection and cleaning of malware in a given data object. This involves providing the necessary detection and cleaning files as well as providing data objects to scan.

An abstract file system is used to make the scan engine system 1300 portable to new devices and enable scanning of many different data objects. More information about ADIR, ADIRENT, and AFILE data objects of the abstract file system will be set forth hereinafter in greater detail.

Table 8 illustrates an exemplary scan engine API.

TABLE 8 SEOpenScanner Description Create an instance of the scanner. The scanner is initialized with files found in the provided pADir. As the scanner doesn't know how to parse file names (being ASCII and Unicode agnostic), the ADIR must filter out any non-PD files. Prototype SCANNER *SEOpenScanner(HDIR hDir); Parameters hDir [in] The supplied HDIR must enumerate only the PD files that are to be used by the scanner. Return Value The function return is an initialized SCANNER data structure. The contents of the SCANNER data structure are internal to the scan engine implementation. See Also SECloseScanner( ) SECloseScanner Description When done using the scanner, it must be closed. This releases any resources that were used by the scanner. Prototype void SECloseScanner (SCANNER *pScan); Parameters pScan [in] pScan is the scanner to close. See Also SEOpenScanner( ) SEScanFile Description Scan the given file for malware. The return value may usually be −1 for no malware detected. Otherwise, SEScanFile returns an identifier for the discovered malware. The returned ID is used with the SECleanFile ( ), SEGetScanName ( ), and SEGetScanVariant ( ) functions. The ID doesn't completely identify the malware as the scanner state holds information about what was discovered. Prototype scan_result_t SEScanFile ( SCANNER *pScan, FILEPATH *pFileName, HFILE hFile); Parameters pScan [in] pScan is the scanner to use. pFileName [in] The name of the file being scanned. hFile [in] The file opened for read access. The hFile may be a specialized interface for reading this type of file. Return Value The returned scan_result_t is an identifier for the malware detected. If malware is not detected, then the return value is −1. See Also SECleanFile( ), SEGetScanName( ), SEGetScanVaraint( ). SECleanFile Description Attempt to repair the given infected file. This can only be called after SEScanFile ( ) to identify malware. The clean function may include deleting the file. Prototype int SECleanFile ( SCANNER *pScan, FILEPATH *pFileName, AFILE *pFile, scan_result_t id) Parameters pScan [in] pScan is the scanner to use. pFileName [in] The file name of the file being scanned. hFile [in] The file opened for read access. Return Values On success, SECleanFile returns Otherwise, it returns −1. See Also SEScanFile( ). SEScanGetName Description Returns the base name of the malware detected. The returned name may change in subsequent calls to SEScanFile ( ). Prototype char *SEScanGetName(SCANNER *pScan, scan_result_t id) Parameters pScan [in] The scan engine used with SEScanFile( ). id [in] The returned ID from SEScanFile( ). Return Values Returns a UTF-8 encoded, zero terminated string. The string is the base name of the malware detected. If no name is available, NULL is returned. See Also SEScanGetVariant( ), SEScanFile( ). SEScanGetVariant Description Returns the variant of the malware detected. Normally this is concatenated with the base name to form the full name of the malware. Prototype char *SEScanGetVariant(SCANNER *pScan, scan_result_t id) Parameters pScan [in] The scan engine used with SEScanFile( ). id [in] The returned ID from SEScanFile( ). Return Values Returns a UTF-8 encoded, zero terminated string. The string is the extended name of the malware detected. Concatenate this to the end of the base name to get the complete name. If no name is available, NULL is returned. See Also SEScanGetName( ), SEScanFile( ). PD File Format

The purpose of this file is to provide the necessary information to detect and clean malware on handheld devices.

The PD file is composed of a header and a collection of records. The header provides general information about the use and management of the PD file. The records contain details about scanning and cleaning malware.

One of the design considerations is that 2-byte entries is desired to be 2-byte aligned, and 4-byte entries to be 4-byte aligned. This resolves some portability issues to processors that can't or have difficulty accessing non-aligned memory references. Note that aligned 4-byte values are not enforced with the instruction byte-code unless the target platform requires it.

Other than keeping the scan engine small, one may also want to support incremental updates for the PD file. One goal is to keep file transfers to the PD devices small.

The following capabilities of Table 9 may be required.

TABLE 9 After the file header, the rest of the file is a list of records New records can be added to the end of the file Records can be marked as free Free records can be re-used for new records Neighboring free records are merged to create a larger free record A record may be moved in memory when updating the contents of that record It's possible that all records may be moved when de- fragmenting the file Avoid re-encrypting the entire file because of a small change An updated checksum needs to be supplied with patches to verify the update File Header

Table 10 illustrates an exemplary file header.

TABLE 10 Bytes Description 48 Copyright notice, end with CTRL + Z 2 Header size 2 Target platform identifier 2 Scan class identifier 2 Reserved. (To be determined - used as 4-byte alignment padding) 4 File version number (major, minor, revision, build) 4 File format version number 4 Date of creation 4 Date of last incremental update 4 Checksum of contents 4 Encryption seed 4 First scan record offset 4 First check record offset 4 First clean record offset 4 First free record offset Header Size

This is used for future expansion. One can add new information to the header without breaking compatibility with older scan engines. This may never actually be used. Byte order for this value is target platform dependant.

Target Platform Identifier

To simplify parsing the PD file on the target machine, the PD file is formatted for the target. The target platform identifier denotes which type of target the file is intended. From this, the following information of Table 11 can be deduced.

TABLE 11 Big-endian or little endian byte order Text encoding format Byte alignment

The only defined combination is the following set forth in Table 12.

TABLE 12 Little endian byte order UTF-8 text encoding 2-byte values are 2 byte aligned, 4 byte values are 4-byte aligned

The definition of Table 12 is used for the target platforms of Table 13.

TABLE 13 Windows variants on IA-32 processors Linux on IA-32 processors Symbian EPOC on ARM processors Scan Class Identifier

The scan class identifier is a value for identifying what class of data the PD file is designed to scan. The following classes of Table 14 are identified at this time.

TABLE 14 Value Description 1 File system 2 Process 3 Data stream Record Header

The records have a common layout to make incremental update simple and aide in finding records without making the scan engine large. An update would send only those records that need to be deleted, replaced, or added. See Table 15.

TABLE 15 Offset Bytes Description 0 2 Record length (N) 2 2 Record type (Scan, name, check, clean, or free) 4 4 Record identifier 8 4 Address of next record of this type (0 if end of list) 12 Record data 0–3 Pad record out to 4-byte align

Instead of referencing parts of the file by address, the PD file uses record ID's. This makes it possible to move a record without having to change every reference to the record.

The record header uses addresses to create a linked list of each type of record. This may help improve performance in finding the proper record. Eventually this could be used to sort records by record ID.

Record lengths are only 2-byte values. This is intentional to make porting between 16-bit processors simple. For example, a mobile wireless device such as a Palm® Pilot™ uses a database instead of a file system. Each record can be at most 64 KB. Nearly all scan functions may be very small. As they get larger, new instructions should be added to the language to move the functionality into the scan engine.

It may be interesting to apply a simple Huffman compression algorithm to the PD byte codes on a record-by-record basis.

Scan Records

This record contains a function for doing an initial scan of the selected file. The amount of code needed for this scan may exceed 64 KB (the maximum record size). Thus, the first scan record starts the process, but may reference other scan records. One goal is to keep the initial scan record small, yet able to eliminate 80% of the clean files. This keeps the scan engine's memory footprint small as well as making efficient use of the processor.

If malware is discovered, the scan function may return the record ID of the name record for this item. This table entry may provide the proper check function to verify the malware variant present. Though this does a double reference, it may not be important. Most of the time is spent eliminating files so that this step may be rare.

Check Records

Check records contain functions for identifying the specific malware variant once identified by the scan records.

The check record starts with the following header information in Table 16.

TABLE 16 Offset Bytes Description 0 4 Record ID of the clean function to call (or 0 if none) 4 2 Number of bytes in name section (N) 6 1 Number of names provided 7 1 Length of malware name, (N0) 8 N0 Text name of the malware 1 Length of variant name (N1) N1 Text name of the variant . . . (Repeat for k variants) 1 Length of variant name (Nk) Nk Text name of the variant 0–1 Pad record out to 2-byte align length N + 4 Instructions for the check function

If no variants are detected, then ˜0 is returned. Otherwise, the index for the variant is returned. A 0 is used if the generic malware detection suffices.

It should be noted that many different check functions can be merged into a single record to reduce the file size if they are sufficiently similar. However, this can cause trouble for incremental updates.

Clean Records

A clean record contains a function for removing the malware and repairing files if possible.

It should be noted that multiple detected malware may use the same clean function.

Free Records

When a record is deleted, it is merged with other free records or added to the free record list. This allows the system to re-use space when performing incremental updates. It solves the problem of re-writing the entire file just because a portion was modified.

Replacing a record is the same as deleting the original, and then adding a new record in its place.

Free records may be set to zero to make predicting the checksum easier.

Activity Logging Module (214 of FIG. 2)

The activity logging subsystem is responsible for recording significant events to be collected at the back-end for analysis. This aids in providing information from the field to track outbreaks, detect and diagnose issues, and help determine how to improve the product.

The following are logged events in Table 17.

TABLE 17 Error conditions and warnings Detection of malware Infected file name and path Malware name and variant Response to malware File name and path Action taken Starting and stopping of services On-demand scan On-access scanner Virus scanner application Service agent upgrades

The detection of and response to malware is separated. Detection is logged immediately when the malware it detected. Once the action is taken and successfully completed, the response is logged. If anything were to go wrong with the response, one would at least see the detection entry.

Adding log file entries is supported at two levels. The most common are functions that handle specific logging needs. These require all the necessary information and add them to the log file with the minimum effort from the programmer. The lower layer manages the log file rotation and a generic mechanism for adding entries.

Configuration

The activity log requires the following configuration values in Table 18.

TABLE 18 Log file rotation size Log file maximum size Log trace messages (yes/no)

A single log file is used until is reaches the log file rotation size. At which point, it is renamed and a new log file is started. Once the total space used by all of the log files exceeds the maximum, the oldest log file is removed. As log files are uploaded from the device, they are deleted from the device.

The log file location and naming conventions are configured per platform when the program is compiled.

Requirements

See Table 19 for possible requirements.

TABLE 19 It must be reasonable to translate the log file to multiple languages. Limit the log file size to a reasonable (configurable) maximum Scroll log file entries as the log file becomes too large (?) Track time and date of log entries Available to the service agent for transmission to the back-end Once transferred, the log file may be truncated. It must be resilient to system crashes Output in a simplified, structured XML format with header for ASCII or UNICODE encoding Enforce log file structure and completeness if information presented Ability to detect when log files have been lost due to exceeding the maximum log file size.

Table 20 illustrates an exemplary interface associated with the activity logging module.

TABLE 20 High level API LogOpen Description Open the log file for reading. Prototype HLOG LogOpen(HVSOPTS opts); Parameters opts [in] A handle to the configuration options manager. Return Value Returns a handle to the log file. It is needed for all of the log functions. If reading the log file, call LogTruncate( ) after the last log file that is successfully transferred from the device. Call LogClose( ) when the log file is no longer being used. If LogTruncate( ) is not called, then the entries may be read the next time LogOpen( ) is called. LogClose Description Closes the log file. This de-allocates all resources related to using the log file. Prototype void LogClose(HLOG log) Parameters log [in] The log file to close. LogMessage Description Adds a message entry into the log file. The type of message is based on LOG_MESSAGE_TYPE. LOG_TRACE is used to help diagnose problems by logging certain milestones in the program. Normally, trace messages are not added into the log file unless configured. LOG_WARNING is provided when a problem is encountered, but does not prevent the proper operation of the program. LOG_ERROR should be used when a recoverable error is encountered. Some functionality of the program may be hindered. LOG_FATAL should only be used when the error is severe, non-recoverable, or prevents the program from running. This may be useful in a post-mortem analysis if the device is returned. Note that the messages are intended for diagnosing field errors by the anti-malware scanner software engineers, and not intended for administrators to understand. Thus, these messages can be in English. Prototype typedef enum { LOG_TRACE, LOG_WARNING, LOG_ERROR, LOG_FATAL } LOG_MESSAGE_TYPE; void LogMessage(HLOG log, LOG_MESSAGE_TYPE type, VSWSTATUS status, char *pMessage) Parameters log [int] This is a handle for the log file. type [in] The type of message being logged. status [int] This is the status code associated with the message. For non-English speaking countries, this may be used to display the error message in the native language. pMessage [in] A UTF-8 encoded, zero terminated string. This is used for extra information our engineers can use to diagnose problems. LogMalwareDetect Description This must be called as soon as malware is detected. The file path must be converted into UTC-8 as a zero terminated string. The scan engine provides malware names and variant names in UTC-8. Prototype void LogMalwareDetect( HLOG log, FILEPATH *pFilePath, char *pMalwareName, char *pMalwareVariant ) Parameters log [in] A handle to the log file. pFilePath [in] This specifies a full description of the infected data object. In a file system, this is the file path. In a database, it uniquely identifies the record. Etc. pMalwareName [in] This is the malware name as returned by SEGetScanName( ). pMalware Variant [in] This is the malware variant as returned by SEGetScanVariant( ). LogMalwareAction Description This must be called once an action to the detected malware is completed. A log entry should also be provided even for ignoring the malware. If the action does not successfully complete, a warning or error message should be added instead. The path provided must be converted to UTC-8. Note that 7-bit clean ASCII text is a subset of the UTC-8 specification. Prototype typedef enum { LOG_CLEAN, LOG_DELETE, LOG_QUARANTEEN, LOG_IGNORE, } LOG_ACTION; void LogMalwareAction(HLOG log, FILEPATH *pPath, LOG_ACTION action) Parameters log [in] A handle to the log file. pPath [in] This is a UTF-8 encoded, zero terminated string. It provides the full path description of the data object identified. This should be the same string as sent to LogMalwareDetect( ). action [in] The action that was successfully completed on the infected data object LogServiceEvent Description This is used to track when services are started and stopped. Tracking these events can help diagnose problems in the field. For example, log entries on starting the application without it being stopped may denote that it crashed and was restarted. Onecan also detect whether the on- access scanner is being disabled and whether the on-demand scanner is being used regularly. More specific milestones should be tracked with the LOG_TRACE messages through the LogMessage( ) function. Unlike the LOG_TRACE messages, the service events are always available in the log file. Prototype typedef enum { LOG_START_SERVICE, LOG_STOP_SERVICE, } LOG_EVENT; typedef enum { LOG_APPLICATION, LOG_ON_DEMAND, LOG_ON_ACCESS, LOG_AGENT, LOG_INSTALL } LOG_SERVICE; void LogServiceEvent(HLOG log, LOG_EVENT event, LOG_SERVICE service) Parameters log [in] A handle to the log file. event [in] Specify whether the service is starting or was stopped. service [in] Specify which service. Low level API The low level API manages the log file rotation and adding generic entries to the log file. This interface is agnostic to what data is added to the log file. The high level API is implemented based on these functions. The first group is for adding entries to the log file. LogOpenEntry LogEntryField LogCloseEntry The above functions are used to create new high-level API functions that are consistent with the subset of XML that is supported. Be careful to define all English words that are used as keywords. This way they can be parsed and translated easily to different languages. This ensures that the raw log file is human readable, though in English, but is easy to also view in any other language. The next group of functions is for consuming log file entries: LogOpen LogRead LogTruncate LogClose LogOpenEntry Description Open a new log entry. Each entry is automatically stamped with the time and date. Prototype HLOGENTRY LogOpenEntry( HLOG log, char *pEntryName) Parameters pEntryName [in] The name that may be used for this entry. This is placed in the log file as follows: <entry-name> [ fields ] </entry-name> Where entry-name is replaced with pEntryName. Return Value A handle to the log entry is supplied, or NULL on error. See Also LogEntryField( ), LogCloseEntry( ) LogEntryField Description Add a field to the given log entry. The field name and value are provided to help structure the log entry. This is useful for generating different tables of information in the log file. Prototype int LogEntryField( HLOGENTRY hLogEntry, char *pFieldName, char *pFieldValue); Parameters pLogEntry [in] This is a handle to the log entry to add the field. pFieldName [in] This is a UTC-8 encoded string for the field-value. It is used as in <field-name>field-value</field-name> pFieldValue [in] This is a UTC-8 encoded string used as the field-value. Return Value The LogEntryField( ) function returns 1 on success, or 0 if it failed to add the entry. LogCloseEntry Description Close the log entry. No more fields may be added to the entry. Prototype void LogCloseEntry(HLOGENTRY hEntry); Parameters hEntry [in] The log entry to close. LogRead Description Read an entry from the log file. Prototype char *LogRead(HLOG log) Parameters log [in] The log file being read. Return Value The returned value a UTF-8 encoded, zero terminated string for the XML entry. It is autonomous in the sense that the caller can stop reading at any time and have a valid XML file from what was read. The returned string is only valid until the next call to LogRead( ). At which point, it may be overwritten with the next entry or de-allocated. A call to LogClose( ) also invalidates the string. NULL is returned if there are no more log entries. LogTruncate Description Remove all entries that were read from the log. This should be used once the log entries are confirmed transferred off of the device. Prototype void LogTruncate(HLOG log); Parameters log [in] A handle to the log file. File Format

The file format may be based on XML. There is a common form that is supported by the low-level API. This is described as follows. Then below, specifics for each type of logged event are provided as well.

Each log file is numbered sequentially. This enables sorting and merging log files, as well as detecting when log files are missing. See Table 21.

TABLE 21 For UNICODE <?xml version=“1.0” encoding=“ISO-10646”?> For ASCII <?xml version=“1.0” encoding=“ISO-8859-1”?> Then the rest: <log id=log_id> <entry-name date=“time-date-stamp”> <field-name> value </field-name> . . . </entry-name> . . .

The strings entry-name and field-name are replaced with the actual entry and field names. The time-date-stamp is the time at which the entry is added to the log file. This is encoded as YYYYMMDDhhmmss, where YYYY is the year, MM is the month, DD is the day of the month, hh is the hour, mm is the minutes, and ss is the seconds.

A sample LogMessage object is shown in Table 22.

TABLE 22 <event date=“YYYYMMDDhhmmss”> <type>message-type</type> <message>message-body</message> </event> message_type is one of trace, warning, error, or fatal. message_body is the text string provided for the message.

A sample LogMalwareDetect object is shown in Table 23.

TABLE 23 LogMalwareDetect <detect date=“YYYYMMDDhhmmss”> <path>file-path</path> <name>malware-name</name> <variant>malware-variant</variant> </detect> file-path is a string identifying where the infected item was found. malware-name is the name of the detected infection malware-variant is the verified variant name of the infection LogMalwareAction <action date=“YYYYMMDDhhmmss”> <path>file-path</path> <action>scanner-action</action> </action> scanner-action is one of “clean”, “delete”, “quarantine”, “ingore”.

A LogServiceEvent is shown in Table 24.

TABLE 24 <service date=“YYYYMMDDhhmmss”> <name>service-name</name> <action>service-action</action> </service> service-name is the name of the service: “on-demand”, “on-access”, “application”, “agent”, “installer”. service-action the word “start” or “stop”. Service Agent

FIG. 14 illustrates a service agent (SA) architecture 1400, in accordance with one embodiment. As shown, a service agent 1402 interfaces with an user interface 1403, an on-access scanner module 1404, and an on-demand scanner module 1406. Such on-access scanner module 1404 and on-demand scanner module 1406, in turn, interface a scan engine 1408.

In use, the service agent 1402 communicates with the back-end architecture 1410 which may be controlled and monitored via a web-interface 1412. The service agent 1402 is thus responsible for communicating with the back-end architecture 1410. It handles delivering device-specific information such as log data to a remote back-end architecture 1410. The second responsibility is in retrieving the anti-malware scanner component installation and package updates. The component manager initiates service agent updates. This may be due to scheduled updates or by user initiated updates.

FIG. 15 illustrates a method 1500 for scanning a mobile wireless device for malware. Initially, in operation 1502, a service agent 1402 is initiated utilizing a mobile wireless device. In one embodiment, the service agent may be initiated by a user interface of the mobile wireless device. Further, the service agent may be initiated by the anti-malware scanner of the mobile wireless device. Still yet, the service agent may be initiated by a daemon of the mobile wireless device. As an option, the service agent may be initiated by a scheduler of the mobile wireless device or a trigger.

Next, in operation 1504, information describing the mobile wireless device is transmitted to a back-end server over a wireless network utilizing the service agent of the mobile wireless device. In one embodiment, the information describing the mobile wireless may include log data. Such log data may be specific to the mobile wireless device.

In operation 1506, an update is then received from the back-end server over the wireless network utilizing the service agent of the mobile wireless device. Optionally, the update may be wrapped. Further, the update may include a header and a plurality of parts. Such parts may include a part-header section and a part-data section.

Subsequently, in operation 1508, an anti-malware scanner installed on the mobile wireless device is updated so that the mobile wireless device may be scanned utilizing the updated anti-malware scanner. More information regarding the foregoing architecture 1400 and associated method 1500 will now be set forth.

Agent Activation Scenarios

FIG. 16 illustrates a sample service agent activation method 1600, in accordance with one embodiment. Depending on the operating system running on the wireless device, the service agent 1602 can be launched by the user-interface 1604, on-demand and on-access scanners 1606, a background process (daemon) and/or system scheduler 1608, itself 1609, and external signal/trigger 1610 originated from the service provider. More information regarding such triggers will now be set forth.

Activation Through User-Interface (Manual Trigger)

The agent can be directly launched from the wireless user-interface by the user. When the user selects an update-now button (or menu entry), the user-interface activates the agent.

Activation by the Agent (Self Trigger)

Under multi-process operating environment, the service agent stays resident and awaits (or sleeps) for update-interval time specified in the anti-malware scanner configuration before contacting the update server.

Scanner Activation (Scanner Trigger)

The agent is launched for new updates when the on-demand and/or on-access scanner notices that the update-interval-time has elapsed since the agent was activated last.

Scheduled Activation (Scheduled Trigger)

Operating system provided scheduler like cron™ in Unix/Linux™ is utilized to schedule the agent activation. Also, if the operating system allows daemon (or background process), a simple daemon is used to activate the service agent.

Carrier/Service Provider Activation (External Trigger)

This is an ideal method for deploying urgent virus signature updates while providing load balance. The wireless device/phone may support launching an application via a signal from its service provider. When an update signal from an external source is received by the device, it launches a pre-configured application, in this case the service agent, for immediate update.

Configuration

Like other the anti-malware scanner components on the device, the agent configuration information is kept in a central location. Table 25 lists the service agent communication configuration and status variables read/updated.

TABLE 25 Variable Example Description server http://update1.mcafeeasap.co Lists one or more update server URL's. m/cgi-bin/update.fcg, http://update2.mcafeeasap.co m/cgi-bin/update.fcg method 1 Specifies server selection method. 0: direct-method—always attempt to connect to the first server given, connect to next server if the first one fails. 1: round-robin—attempt to connect to server listed after previous connected server. last_connect 167.68.79.100 IP address port number of the last update server successfully connected. last_check 20020110051530 Last time the agent made a successful server connection. Format: YYYYMMDDhhmmss connect_timeout 5000 Server connection timeout in milliseconds. read_timeout 3000 Socket read timeout value in milliseconds. write_timeout 3000 Socket write timeout value in milliseconds. connect_retry 5 Maximum connection open retry count. read_retry 3 Maximum socket read retry count. write_retry 3 Maximum socket read retry count. download_dir X$/vswsa/download Where to store downloaded package. Service Package

The term “package” refers to any data/information uploaded/downloaded to/from a remote update server. Each package is made up of a header and parts. Each part consists of part-header and part-data sections. Designed for simplicity, endian-ness independence, and extensibility, the anti-malware scanner package format is an HTTP-like transmission format that allows multiple inclusion of any types of data. The package format is composed by subsequent entries:

Table 26 illustrates an exemplary format.

TABLE 26 Format <PART₀> . . . <PART_(n)> with each part is composed of: <PART-HEADER> <PART-DATA> The end-of-file marks the end-of-package data. Package and part header section has the following format: <FIELD_(n)> ‘:’ <SP> <VALUE_(n)> <CRLF> . . . <CRLF> where: <FIELD_(n)> :: $NAMETOKEN <SP> :: [\b] (space character) <VALUE_(n)> :: $VARTOKEN <CRLF> :: “\r\n” (carriage return followed by linefeed) and: $NAMETOKEN :: [a–z, A–Z, 0–9] $VARTOKEN :: [{circumflex over ( )}\r\n] Between the <FIELD> values, two are mandatory: ContentName: ENRTY-NAME ContentLength: LENGTH where:

-   ENRTY-NAME is the object identification name, and -   LENGTH is the length of the subsequent DATA section in bytes.

The part-data section is made up of a binary chuck of data whose length is LENGTH.

The format described above simplifies package creation and information access thus keeping the device application footprint small.

The part-header section can contain other useful information, for example, content type, compression method, signatures, checksums, etc. Also, it's possible to contain information that does not carry any data by setting the ContentLength: to zero and by making the <FIELD> carry data. As given in the example of Table 27, the device identification number is uploaded to a server by setting the ContentName to $DEV-UID, including a field names X-DEVUID, and setting the ContentLength to zero. See Table 27 for a package containing device ID number.

TABLE 27 ContentName: $DEV-UID X-DevUID: 091200831080281 ContentLength: 0

The content name part can easily contain pathname information that make the format suitable for multi-level packaging transfers. Table 28 shows an example package uploaded to a server. It contains three separate information: 1) device identification number, 2) device log information, and 3) product and component version information (catalogue).

Upload Package

Three types of part contents are uploaded to a server for back-end processing are: 1) device identification number, 2) device system/log information in XML format, and 3) component version information. The device identification number is used by the back-end to validate a device connection. Uploaded system and log information is processed and stored in a back-end database for reporting. Product/component version information, catalogue, is used by the back-end server in selecting an installation package to download.

TABLE 28 Content Required Name Field Description $DEV-UID X-DevUID Contains 16-byte device identification number given in the X-DevUID field. Content length is always zero. $DEV-LOG none Contains system activity and virus detection log information to be stored in the back-end database. $DEV- none Virus signature database version, CATALOGUE scan engine version numbers, and other component and product version information is included in the catalogue. The back-end update server uses the version information uploaded in determining whether to download a new installation package.

The upload package is created from data provided by individual components that are registered with the service agent to upload/report its information to the back-end server. The service agent simply requests the registered components for upload data. Table 29 illustrates sample upload parts.

TABLE 29 ContentName: $DEV-UID X-DevUID: 091200831080281 ContentLength: 0 ContentName: $DEV-LOG ContentType: text/xml ContentLength: 1252 <?xml version=“1.0” encoding=“ISO-8859-1”?> <log> <event time=“20020110110323”> <severity>0</severity> <message>Device was updated successfully</message> </event> <scan time=“20020110121545”> <name>Nasty</name> <type>trojan</type> <action>2</action> <infected>Address.prc</infected> </detect> . . . </log> ContentName: $DEV-CATALOGUE ContentType: text/xml ContentLength: 815 <?xml version=“1.0” encoding=“ISO-8859-1”?> <catalogue> <product> <id>7002</id> <version>1.0</version> <name> Wireless</name> </product> <component> <name>engine</name> <version>4.10.08</version> </component> <component> <name>PD</name> <version>4288</version> </component> . . . <catalogue> Client Authentication/Verification

The server uses the device identification number specified by the X-Device-UID field to verify and retrieve client-specific information. This verification is done as soon as any part of the HTTP POST data containing the device identification is received.

Event Log

Also given in the client upload package is a wireless component/application log entries. Like the catalogue information, the log entries are formatted in XML form. There are two types of log entries: detection log and application event log. The detection log entry contains detected malware name, its type, infected filename, and the action taken by the scanner. Application (or component) event log entry lists severity of the event and a short message describing the event. Both the detection and the event log entries have a timestamp specified in UTC. Table 30 illustrates a pair of XML formats.

TABLE 30 Format 1 Event Log Entry Format <event time = “YYYYMMDDhhmmss”> <severity>severity-value</severity> <message>event-description</message> </event> Format 2 Detection Log Entry Format <detect time=“YYYYMMDDhhmmss”> <name>malware-name</name> <type>malware-type</name> <infected>infected-file</infected> <action>scanner-action</action> </detect>

The log entry time stamp given in UTC has the following format in Table 31.

TABLE 31 YYYY :: year (e.g. 2002) MM :: month (01–12) DD :: day of the month (01–31) hh :: hour of the day in 24 hour format (00–23) mm :: minute (00–59) ss :: second (00–59)

Table 32 illustrates a sample log.

TABLE 32 ContentName: $DEV-LOG ContentType: text/xml ContentLength: 659 <?xml version=“1.0” encoding=“ISO-8859-1”?> <log> <event date=“20020108110323”> <Severity>0</severity> <message>PD updated</message> </event> <detect date=“20020108110645”> <name>Nasty</name> <type>virus</type> <infected>paint.exe</infected> <action>cleaned</cleaned> </detect> <detect date=“20020108110815”> <name>Nimda</name> <type>trojan</type> <infected>hello.exe</infected> <action>deleted</cleaned> </detect> <event date=“20020108111010”> <Severity>2</severity> <message>failed to scan kernel32.exe</message> </event> <log> Component Catalogue

The device catalogue (version information) uploads lists on the anti-malware scanner components. This catalogue information along with the device identification number is used in constructing a download package for the specific-device/client. Each catalogue entry given in the client upload package follows the format in Table 33.

TABLE 33 <catalogue> <product> <id>product-id</id> <version>version-number</version> [<name>product-name</name>] </product> <component> <id>component-id</id> <version>version-number</version> [<name>component-name</name>] </component> . . . </catalogue> Upload Information Gathering

Except for the device identification information, the service agent does not directly generate or format the data in the upload package—the service agent uploads data obtained from its clients. The service agent uses a set of callback functions supplied by its caller (or client) to request upload information. The service agent API SaSetParameter (and SaSetParameters) is used to by service agent client(s) to specify how to obtain upload data from each component.

Below steps describe the upload process

-   A. Initialization     -   1. each client is notified by the SA to construct a package part         to upload.     -   2. the SA prepares package header that contains total package         size information     -   3. device-identification part is constructed -   B. Login     -   1. connect to a remote server     -   2. send package header and device-identification part $DEV-ID -   C. Transmit     -   1. For each registered client, request a block of data from the         client and then transmit. -   D. Cleanup -   E. Notify clients upload status     Package Download

After uploading a package, the service agent awaits for the server to download an installation package. The package header specifies the total package size, and the SA uses it to determine if the package contains installation part(s). The package size specified is greater zero, the SA downloads and saves the entire package data onto a download directory and calls the component installer. Each install part in an install package is identified by the content name that specifies the data format. The installer uses the format identifier in selecting an appropriate unpacker/decompressor for extracting and installing files contained in the part. Table 34 illustrates a sample installation package.

TABLE 34 ContentName: $INST-SIS ContentType: binary ContentLength: 200105 [200,105 byes of SIS data] Client-Server Communication

FIG. 17 provides a method 1700 for client and server package handling. As shown in FIG. 17, during a client process 1701, a package is prepared by a mobile wireless device to be uploaded. See operation 1702. This client package is then posted for access by the server in operation 1704. This prompts the initiation of a server process 1705.

During the server process 1705, the client package is received in operation 1706, after which the client is verified in operation 1708. If an error is detected in decision 1712, an error message is posted in operation 1710. If not, however, the database is updated based on the client package in operation 1714. Next, a server package is generated in operation 1716, after which the server package is posted for access by the client in operation 1718.

The client process 1701 then proceeds by receiving the server package in operation 1720. If an error is identified in decision 1722, the process is terminated. If, however, no error is detected, the contents that are listed in operation 1724 are installed in operation 1726. Further, the catalogue is updated in operation 1728.

The client-server communication is thus initiated by the service agent by posting an upload package to a remote server. When this HTTP(S) POST is made to the server, the client connection is verified and the entire client package is received. After receiving the client package, the server updates database with the uploaded information, and then returns a package generated based on the information uploaded. The client installs components in the server package and updates its installed component catalogue.

Client-Server Protocol

The device update process may take place by preparing the package format (MPF) that may be basically composed by an UID entry, an XML file containing device catalogue information like dat/engine/applications versions and log entries and eventually quarantine files.

Once the package is prepared, the service agent (SA) may lookup its configuration searching for the URL to which to post the request. The URL may have the form shown in Table 35

TABLE 35 http://CARRIERDOMAIN/cgi-bin/update.fcg or https://CARRIERDOMAIN/cgi-bin/update.fcg

for HTTP over SSL connections. The package may be sent to the remote back-end agent (RBA) with a standard HTTP POST request like given that in Table 36.

TABLE 36 POST <CARRIERDOMAIN>/cgi-bin/update.fcg HTTP/1.0 Host: <CARRIERDOMAIN> Content-Type: binary/MPF X-Device-UID: <DEVICE-UID> Content-Length: <SIZEOF-PACKAGE> [<SIZEOF-PACKAGE> bytes of binary data]

After that, the RBA may be invoked and it may unpack the package looking for the catalogue information coming from the device (i.e. details of what happens inside the RBA are described in another document). Based on the device current catalogue, the RBA may prepare a custom package whose format may be device dependent to better utilize intrinsic device capabilities and hence reduce the code footprint of the SA application. The RBA may send the prepared package as data inside the HTTP POST response given in Table 37. Then, the connection to the RBA may be closed and the SA may be free to process the package.

TABLE 37 POST <CARRIERDOMAIN>/cgi-bin/update.fcg HTTP/1.0 Host: <CARRIERDOMAIN> Content-Type: binary/MPF X-Device-UID: <DEVICE-UID> Content-Length: <SIZEOF-PACKAGE> [<SIZEOF-PACKAGE> bytes of binary data] HTTP/1.0 200 OK Host: <CARRIERDOMAIN> Content-Type: binary/MPF Content-Length: <PACKAGE-SIZE> [<PACKAGE-SIZE> bytes of binary data] Secure Communication and Authentication

The service agent uses system-provided secure channel (e.g. SSL) for server communication and authentication APIs for downloaded package verification. Data uploaded from a device to a server is done through secure channel to protect private information. The download package containing virus detection files and component upgrades need to be cryptographically signed and authenticated. Without proper authentication, the device may be vulnerable to a third party attack.

Table 38 illustrates an exemplary service agent API.

TABLE 38 SaOpen Description The SaOpen( ) call creates a service agent(SA) instance and returns its handle. The returned handle must be released using the SaClose( ) call. Prototype HSAgent SaOpen(SAMODEL model, HVSOPTS hOpts); Parameters model [in] specifies the created service agent's run-time process model. Below list describes the service agent run-time models. SAMODEL Description SARUN_SPS Instantiated service agent resides in the caller's process space. The caller needs to make subsequent SA calls for update, installation and status queries. SARUN_FORK SaOpen spawns/forks a service agent process. The SA process stays resident until SaClose is called. This run-time model is supported only under multi-task/multi-process OS such as Unix/Linux and Windows NT/2K. SARUN_DEF Specifies the system default run-time model. SaOpen selects either SARUN_SPS or SARUN_FORK depending on the system implementation HVSOPTS [in] application configuration/option handle. Table below provides the service agent run-time configuration options obtained from the configuration handle. Configuration Name/Reference Value Type Description SAPAR_INTERVAL UINT16 Service interval in minutes. Supported under SAMODE_FORK model. SAPAR_SERVERS SASERVERS Specifies servers to contact for upload/download. SASERVERS is defined as typedef struct { int   nServers; URL*  pList; } SASERVERS; Where URL is typedef struct { char* pszURL; } URL; This parameter overrides server listed in the configuration settings. SAPAR_SELECT BYTE Server selection method 0 for direct-mode (first-listed first) 1 for round-robin This parameter overrides CFG_SERVER_SELECT setting in the system configuration. SAPAR_TIMEOUT UINT32 Server communication timeout in milliseconds. This parameter overrides CFG_SERVER_SELECT setting in the system configuration. SAPAR_TEMP PATHSTR System temp directory path. This parameter overrides CFG_SERVER_SELECT setting in the system configuration. SAPAR_DOWNDIR PATHSTR Where to store downloaded package. This parameter overrides CFG_SERVER_SELECT setting in the system configuration. Return Value A handle to the instantiated service agent. NULL indicates failure. See Also SaClose SaClose Description SaClose releases system resources used by a service agent handle. If the SA is running as a separate process, SARUN_FORK model, the process is terminated. Prototype int SaClose(HSAGENT hAgent); Parameters hAgent [in] service agent handle returned by SaOpen Return value 0 on success. −1 indicates error. See also SaOpen SaSetDnCallback Description Used to specify a callback function during a package download process. Prototype int SaSetDnCallback(HSAGENT hAgent, FNSADNPARTCB* pfnCallback); typedef int (*UpPartCallback)(    char* pszPartName,    size_t partSize,    size_t totalSize, ) SADNPARTCB; Parameters hAgent [in] service agent handle returned by SaOpen pfnCallback [in] If set, the service agent calls the function specified for each part downloaded from a server. If the callback function returns −1, the agent aborts the download process. pszPartName downloaded part name partSize downloaded part size totalSize download package size Return value 0 on success. −1 indicates error. See also SaOpen, SaSetUpHandlers SaRegClients Description The SaRegClients is used by the caller to specify a list upload clients. The service agent obtains upload data and related information via a set of callback functions that define an upload client. Prototype int SaSetUpHandlers( HSAGENT hAgent, FNSAUPPARTCB*   pfnCallback, SAUPPERTCLIENT*  clients, int howMany ); typedef int (*UpPartCallback)(    char* pszPartName,    size_t partSize,    size_t totalSize,    int nPartNum,    int nParts ) FNSAUPPARTCB; typedef struct {    char* pszPartName;    int (*Initialize)(void);    size_t (*PartSize)(void);    int (*GetData)(     void* buffer,     size_t cbBuffer,     size_t* pcbSize     );    int (*Cleanup)(BOOL bSuccess);    int (*Result)(BOOL bSuccess); } SAUPPARTCLEINT; Parameters hAgent [in] Service agent handle returned by SaOpen. pfnCallback [in] if specified, the service agent periodically makes calls the ‘pfnCallback’ function during the upload process with the following parameters: pszPartName name of the part uploaded (or being uploaded) partSize part data uploaded (in bytes) totalSize total upload package size (in bytes) nPartNum part handler number listed in the upload handler list ‘handlers’ nParts total number part handlers listed (= ‘howMany’). If the callback function returns −1, the service agent aborts the update process. clients [in] a list components involved in uploading information to a server. When an upload package is prepared by the service agent through a scheduled event or by a request by another component/application, the service agents goes through the upload “clients” given as the ‘clients’. A SAUPPARTCLIENT structure contains callback functions the agent makes to a client when preparing and sending upload-data (or part). The Initialize call is made by the service agent to notify each upload client to prepare data to upload. The PartSize is used to query upload-data size. The GetData is called by the service agent to request a block of upload-data from its owner (or client). The Cleanup call is made to notify the client after entire data has been uploaded to a server. The parameter nError is set to zero if the upload process was successful. −1 to indicate failure. pszPartName upload component/part name passed to the ‘pfnCallback’ Initialize informs the upload handler to prepare data to send PartSize request the upload part size GetData request a chunk of upload data from the handler Cleanup informs the handler its part/data has been successfully uploaded or failed Result informs the handler whether the entire upload process was successful The service agent, when ready to send a given upload part, calls the Initalize function to let its client know that it needs to prepare a upload data, and then requests the size of the upload part/data. The GetData function is used by the service agent to request a chunk of upload data client. The data received is immediately uploaded to a server. The Cleanup is called when entire upload data for the client has been transmitted or an error occurred. When all the component upload parts have been uploaded, the service agent informs listed clients using the Result callback function. howMany [in] specifies the number of upload clients listed Return Values 0 to indicate success. −1 to indicate failure. See also SaSetDnCallback, SaUpdate SaUpdate Description The SaUpdate call performs three tasks: 1) device to server package upload, 2) server to device package download, and 3) package installation. The device's upload package is prepared using the upload part handlers specified using the SaRegClients and SaSetDnCallback calls. After uploading a device package, SaUpdate downloads and installs a package containing wireless components from a server. Prototype int SaUpdate( HSAGENT hAgent, BOOL* pbPkgInstalled ); Parameters hAgent [in] Service agent handle returned by SaOpen. pbPkgThere [out] TRUE if a package has been downloaded and installed successfully. Return Values 0 to indicate success. −1 to indicate failure. See also SaRegClients, SaSetDnCallback SaState Description The SaState call returns the service agent's state. This call provides the caller with current operation being performed by the service agent under the SARUN_FORK model. Prototype SASTATE SaState(HSAGENT hAgent); Parameters hAgent [in] service agent handle returned by SaOpen Return value Returns one of the states listed below. SASTATE Meaning SAST_NOTIMPL Not implemented - OS does not multi- tasking/process. SAST_ERROR Failed to obtain the service agent state. SAST_STANDBY Waiting for service interval or waiting for call to SaUpdate. SAST_UPDATE Uploading/download package to/from a server. SAST_INSTALL Installing downloaded package. SAST_ABORTING Processing SaAbort request. See also SaUpdate, SaAbort SaAbort Description The SaAbort call aborts package upload/download and installation. This call is not supported under single-task/process model SARUN_SPS. If SaAbort is called during a upload process, each registered upload part handler is notified Prototype int SaAbort(HSAGENT hAgent); Parameters hAgent [in] service agent handle returned by SaOpen Return Values 0 if successful. −1 indicates error. See also SaUpdate, SaState Installer

The anti-malware scanner installer is tasked with extracting and installing components. This includes the update or install packages the service agent receives from a back-end server. The configuration manager coordinates between the service agent and the installer to retrieve updates, and shuts down the on-access scanner so as not to cause a conflict when installing components.

Installation Package

The installation package contains one or more wireless installation components encapsulated in parts. Each part contains binary image of the component, version information, and special pre/post scripts used to install the component. The installation package format and its part format is identical to the service package uploaded to a server by the service agent.

One exemplary format is shown in Table 39.

TABLE 39 The installation package is made up of multiple parts: <PART₀> . . . <PART_(n)> Each installation part is made up of part-header and part-data: <PART-HEADER> <PART-DATA> Installation part-header is made up of part-data and component description: ContentName: <content-identifier> ContentType: <content-type> ContentLength: <content-length> ComponentID: <component-ID> ComponentName: <component-name> ComponentVersion: <component-version>

The content-identifier uniquely identifies the content information, content-type describes the content format/type of the part-data, and content-length provides the length (in bytes) the part-data included. Component-id is the wireless component identification number used in referencing a particular component, component-name specifies the component name, and component-version provides the version information. The example of Table 40 is an installation package containing PD and engine updates. The first part contains the virus signature file scan.pd, and the second part contains scan engine update with pre and post installation scripts to execute when installing the engine.

Content Name

The installer uses the content names in identify the install algorithm. Table 40 lists the content names accepted by the installer.

TABLE 40 Content Name Description $ENGINE scan engine $PD virus signature database $PDn virus signature database containing a limited set of detections; where 0 ≦ n $PDU virus signature database update $APP Wireless application $CONFIG Wireless application configuration $APP-1 contains an application to be executed and removed (e.g. special virus cleanup app) $PRE-SCRIPT script/application to be executed before a component is installed $INST-SCRIPT script/application for installing the component; default install algorithm is by passed when this script/app is included $POST-SCRIPT script/application to be executed after installation Content Type

The content type provides the stored part-data (component install image) format type, either binary or text, and the component classification names. Table 41 lists the component classification names used in an install package.

TABLE 41 Content Type Description pd-file virus-signature data container part-data containing one or more parts script system-specific script file lib run-time library (e.g. DLL) app application binary Component Identification

The component identification specifies the wireless component number. It is used to reference a specific component in the wireless component catalogue on the device. See Table 42.

TABLE 42 Component ID Description 1000 full virus signature database 1001, . . . , 1099 virus signature database subset 2000 scan engine 3000 main application 5000, . . . , 5999 special applications ContentName: $PD ContentType: binary/pd-file ContentLength: 156 Component ID: 2000 ComponentName: PD ComponentVersion: 2.0.1 [156 bytes long scan.pd image] ContentName: $ENGINE ContentType: binary/container ContentLength: 650 ContentPriority: 0 ComponentID: 1000 ComponentName: scan engine ComponentVersion: 4.3.21 ContentName: $PRE-SCRIPT ContentType: text/script ContentLength: 35 /etc/rc.d/init.d/vmax stop ContentName: $BINARY ContentType: binary/lib ContentLength: 256 [256 bytes long scanengine image] ContentName: $POST-SCRIPT ContentType: text/script ContentLength: 34 /etc/rc.d/init.d/vmax start Installation Process

FIG. 18 illustrates the various steps 1800 of the package installation process, in accordance with one embodiment. Once an installation/update package has been downloaded, the service agent notifies the installer to extract and install/update new components. See operation 1802.

-   1. obtain package information     -   a. enumerate through enclosed contents/parts (1804)     -   b. order components by priority -   2. notify components -   3. for each component:     -   a. extract components to a temporary storage (1806)     -   b. execute pre-install script if included (1808)     -   c. copy/move extracted component     -   d. update catalogue     -   e. execute post-install script -   4. notify components -   5. cleanup (1812)

The installation notification is sent out to components running on the device before and after an installation. See operation 1810. The notification information includes the component identification number of the component being updated.

Installer API

An illustrative installer API is shown in Table 43A.

TABLE 43A InsPackageInstall Description The InsPackageInstall call installs the anti-malware scanner installation package. Prototype int InsPacakgeInstall(void); Parameters none Return Values 0 on success. −1 indicates error. Platform Abstraction Layer (218 of FIG. 2)

The wireless platform abstraction layer (PAL) is a middle-ware API designed to provide components with a platform-independent system interfaces. The abstraction layer is divided into following seven categories.

FIG. 19 illustrates the components 1900 of the platform abstraction layer 1902 and the manner in which they interface with the mobile wireless device 1904 and operating system 1906 thereof. See Table 43B for a list of such components.

TABLE 43B 1. Storage I/O APIs for accessing files (or stored objects) and directories, (1908) 2. Dynamic memory allocation APIs, (1910) 3. Process/task control calls (1912) 4. Network I/O calls (1914) 5. System event handler APIs (1916) 6. System identification and resource information routines (1918) 7. Miscellaneous APIs (1920)

More information will now be set forth regarding the various components of the platform abstract layer.

Storage I/O (1908 of FIG. 19)

Storage I/O API is used by wireless to access and modify data objects (or files) stored on a non-volatile storage device (e.g. flash memory, hard disk) and managed by a file system or file system like storage and retrieval system. The API is divided into three categories: 1) I/O routines for reading/writing data to/from single object or file, 2) calls used to copy, move and delete a stored object, 3) and routines that provide object enumeration from a storage. See Table 44.

TABLE 44 Name Arguments Returns Description FsFileOpen const FILEPATH* HFILE Opens the specified file using the specified. pFilePath, FILEPATH is a system-specific data fmode_t modes, structure used to define a specific-file path. FsFileClose HFILE hFile In. Closes specified file handle. FsFileRead HFILE hFile, size_t Returns the number of bytes read into void* buffer, ‘buffer’ after attempting to read ‘cbLength’ size_t cbLength from file handle ‘hFile’. (size_t) − 1 is returned on error. FsFileWrite HFILE hFile, size_t Returns the number of bytes written from void* buffer, ‘buffer’ after attempting to write size_t cbLength ‘cbLength’ bytes to file handle ‘hFile’. (size_t) − 1 is returned on error. FsFileSeek HFILE hFile, off_t Returns current file handle offset position off_t offset, after moving ‘offset’ bytes from the fpos_t whence location directive ‘whence’. (off_t) − 1 is returned on error. FsFileSetSize HANDLE hFile, off_t Sets the files size to ‘cbNewLength’ bytes off_t long. −1 is returned on error. cbNewLength FsFileDelete const FILEPATH* int Deletes the specified file. pFilePath −1 is returned on error. FsFileRename const FILEPATH* int Renames a file, moving it to different pOldPath, directory if required. const FILEPATH* If a file with same path exists, the call pNewPath returns an error. −1 is returned on error. FsFileCopy const FILEPATH* int Copies a file to a different location. If pSrcPath, ‘bOverwrite’ is not set (= FILE) and a const FILEPATH* destination file exists, an error is returned. pDestPath, BOOL bOverwrite FsFileCopyToDir const FILEPATH* int Copies a file to the specified directory pSrcPath, location. If ‘bOverwrite’ is not set (= FILE) const DirPATH* and a destination file exists, an error is pDestDir, returned. BOOL bOverwrite FsFileStat const FILEPATH* int Returns information (including file size, pFilePath, permission) on specified file. FILESTATE* pFileStat FsSetMode const FILEPATH* int Sets the file access permission to the mode pszPath, specified. faccess_t accessMode FsDirRoot void HDIR Returns the root directory handle. FsDirOpen const DIRPATH* HDIR Returns a directory handle for the specified pDirPath directory. FsDirClose HDIR hDir int Releases resource taken up by a directory handle. FsDirFirst HDIR hDir const Returns the first directory entry. DIRENTRY* FsDirNext const DIRENTRY* const Returns the directory entry listed after the pDirEntry DIRENTRY* entry pointed by the ‘pDirEntry’ pointer. FsGetFilePath void* buffer FILEPATH* Converts system-specific file path into the FILEPATH structure and returns its memory pointer. The returned pointer needs to be released using the FsFreeFilePath. FsFreeFilePath FILEPATH* int Frees system resource associated with the pFilePath structure pointed by ‘pFilePath’ pointer. FsGetDirPath void* buffer DIRPATH* Converts system-specific directory path into the DIRPATH structure and returns its memory pointer. The returned pointer needs to be released using the FsFreeDirPath. FsFreeDirPath DIRPATH* int Frees system resource associated with the pDirPath structure pointed by ‘pDirPath’ pointer. Network Socket I/O (1914 of FIG. 19)

See Table 45 for an exemplary network socket I/O API.

TABLE 45 Name Arguments Returns Description SocketOpen int domain, HSOCKET Creates a network socket and returns its int type, handle. int protocol SocketConnect HSOCKET hSocket, int Initializes connection on a socket. msec_t timeout, −1 returned if error. SockAddr sockAddr, NETPORT_T port SocketBind HSOCKET hSocket, int Sets the socket to bind to port ‘port’. NETPORT_T port Client IP address is set to INADDR_ANY. −1 returned if error. SocketAccept HSOCKET hSocket, int Accepts a connection on a socket and SOCKADDR* pAddr returns connected client IP information in ‘pAddr’. −1 returned if error. SocketReceive HSOCKET hSocket, size_t Reads from a connected socket. msec_t timeout, void* buffer, size_t size SocketSend HSOCKET hSocket, size_t Writes to a connected socket. msec_t timeout, void* buffer, size_t size SocketClose HSOCKET hSocket int Closes connection and releases system resource. SSLOpen HSOCKET hSocket HSSL Transforms a normal (non-secure) socket to a SSL socket, and the SSL API calls should be used instead. If the call fails, the ‘hSocket’ property is retained and NULL is returned. SSLConnect HSSL hSocket, int Initializes connection on a SSL msec_t timeout, socket. SockAddr −1 returned if error. sockAddr, NETPORT_T port SSLAccept HSSL hSocket, int Accepts a SSL connection on a SSL socket and SOCKADDR* pAddr returns connected client IP information in ‘pAddr’. −1 returned if error. SSLReceive HSSL hSocket, size_t Reads from a connected SSL socket. msec_t timeout, void* buffer, size_t size SSLSend HSSL hSocket, size_t Writes to a connected SSL socket. msec_t timeout, void* buffer, size_t size SSLClose HSSL hSocket int Closes SSL connection and releases system resource. Process Control API (1912 of FIG. 19)

See Table 46 for an exemplary process control API.

TABLE 46 Name Arguments Returns Description ProGetList pid_t** ppPid int Returns the number of current system processes and a list of process id's. ProFreeList pid_t* pPid int Frees process listed obtained using ProGetList. ProKill pid_t pid int Terminates specified process. ProOpen pid_t pid HPROCESS Returns a process handle corresponding to the process id. ProClose HPROCESS int Frees resource associated with the hProcess process handle. ProGetName HPROCESS int Returns process name. hProcess, void* pName, size_t cbName ProGetFilePath HPROCESS int Returns storage path for the process hProcess, image. FILEPATH** ppFilePath ProGetCodeMem HPROCESS size_t Retrieves ‘cbRead’ bytes of process hProcess, instruction code/data from process code size_t offset, offset ‘offset’. Returns the number of void* buffer, bytes read into ‘buffer’. size_t cbRead Return value (size_t) − 1 indicates error. Dynamic Memory (1910 of FIG. 19)

See Table 47 for an exemplary dynamic memory API.

TABLE 47 Name Arguments Returns Description MemMalloc size_t size void* Returns a pointer to at least ‘size’ bytes long dynamic memory block. MemFree void* ptr void Frees dynamic memory allocated using MemMalloc Event Handler API (1916 of FIG. 19)

See Table 48 for an exemplary event handler API.

TABLE 48 Name Arguments Returns Desciption EvntSetHandler int event, int Sets a callback/handler for FNEVENT_HANDLER* event ‘event’. pFunc EvntGetHandler int event FNEVENT_HANDLER* Returns event handler for event ‘event’ System Information (1918 of FIG. 19)

See Table 49 for an exemplary system information API.

TABLE 49 Name Arguments Returns Description SysGetId unsigned char int Obtains 16-byte device id[16] identification code.

See Table 50 for an exemplary error/status API.

TABLE 50 Name Arguments Returns Description ErrSetLast VSWSTATUS err int Sets the last error to ‘err’ ErrGetLast void VSWSTATUS Returns the last error set using the ErrSetLast function. Misc. API (1920 of FIG. 19)

See Table 51 for an exemplary misc. API.

TABLE 51 Name Arguments Returns Description Sleep msec_t msec int suspends current execution and sleeps for ‘msec’ milliseconds MemSet void* dest, void* Sets the first ‘n’ bytes of memory pointed by int pattern, ‘ptr’ to ‘pattern’. size_t n Pointer to ‘ptr’ is returned. MemCopy void* dest, void* Copies ‘n’ bytes from memory area ‘src’ to void* src, memory area ‘dest’ and then returns pointer to size_t n ‘dest’. ExecBuffer void* buffer, int Treats the ‘buffer’ as executable binary image and size_t length requests the system to execute. The return code of the executable is returned. ExecFile const FILEPATH* int Request the system to execute the executable file identified pExePath by ‘pExePath’. The return code returned by the executable is passed on to the caller. Abstract File System Specification

The abstract file system provides an interface for supporting features in the platform abstraction layer (PAL). When porting the anti-malware scanner to new platforms, this interface may need to be implemented for every class of scannable data object on the device. The most common may be a file system. This may also include databases or custom persistent data storage on the device.

Implementing the Interface

The scanner components use the HDIR and HFILE handles to interact with files and directories. These handles are discussed in greater detail in the PAL. The abstract file system is one way of implementing these handles.

Three different interfaces need to be supported, as shown in Table 52.

TABLE 52 Abstract Directory: ADIR Abstract Directory Entry: ADIRENT Abstract File: AFILE

The ADIR is used to support HDIR. The ADIRENT supports both FILEPATH and DIRPATH. The AFILE supports HFILE.

For example, an HDIR is type cast into an ADIR pointer.

Thus, FsFileRead( ) can be defined as follows in Table 53.

TABLE 53 #define FsFileRead(hFile, pBuffer, length) \ ((ADIR*)hFile ) ->pRead(hFile, pBuffer, length)

This saves on the overhead of having to implement a FsFileRead( ) function that does essentially the same thing as the macro.

ADIR, ADIRENT, and AFILE are implemented as data structures with callback functions. The callback functions provide basic capabilities to enumerate and manipulate files. The calling application must implement these interfaces.

Data Types

See Table 54 for various exemplary data types.

TABLE 54 ADIRENT_TYPE Description Denotes the type of ADIRENT. Prototype enum ADIRENT_TYPE { ADIRENT_UNKNOWN = 0, ADIRENT_AFILE = 1, ADIRENT_ADIR = 2 }; AFILE_MODE Description When opening a file, the read/write mode must be specified. It can be changed later with a call to AFILE.setmode( ). For scanning files, the mode should be read only. However, to clean the file, the mode may be changed to read/write if possible. Prototype enum AFILE_MODE { AFILE_READ_ONLY = 1, AFILE_WRITE_ONLY = 2, AFILE_READ_WRITE = 3, };

ADIR Interface

See Table 55 for an exemplary ADIR API.

TABLE 55 ADIR Description This interface provides an abstract directory. This is anything that has entries that can be enumerated like a directory structure. Prototype struct ADIR { ADIRENT *(*pOpenFirst)(ADIR *pADir); ADIRENT *(*pOpenNext)(ADIR *pADir); void (*pClose)(ADIR *pADir); }; Example Internally, it may be useful to create a structure for holding private data members for the ADIR structure. For example, typedef struct {  /*public*/  ADIR adir;  /*private*/  char *pPath;  char *pFilter;  glob_t glob;  int index; } PDIR; A function is needed to initially create an ADIR of any given type. The following shows how the data structure is allocated and initialized under UNIX systems. ADIR *open_std_dir(const char *path, const char *filter) {  PDIR *dir = malloc(sizeof(PDIR));  if(dir != NULL)   {    memset(dir, 0, sizeof(PDIR));    dir−>pPath = strdup(path);    if(filter != NULL)     dir−>pFilter = strdup(filter);    dir−>adir.pOpenFirst = dir_open first;    dir−>adir.pOpenNext = dir_open_next;    dir−>adir.pClose = dir_close;   }  return (ADIR*) dir; } pOpenFirst Description Open the first entry in the directory. The directory entries might not be sorted. This function merely starts the enumeration of entries. Example In the above example, adir−>pOpenFirst points to the dir_open_first( ) function: static ADIRENT *dir_open_first(ADIR *adir) {  PDIR *dir = (PDIR*)adir;  char *pattern;  pattern = malloc(strlen(dir−>pPath) + strlen(dir−>pFilter) + 1);  if(pattern != NULL)  {   strcpy(pattern, dir−>pPath);   strcat(pattern, dir−>pFilter);   if(glob(pattern, GLOB_MARK|GLOB_NOSORT, NULL, &dir->glob) == 0)    { dir−>index = 0; free(pattern); return dir_open_next(adir);    }   free(pattern);  }  return NULL; } pOpenNext Description Get the next entry in the directory. It may be necessary to close the prior entry before opening another entry. Returns NULL when no more entries are available. Example static ADIRENT *dir_open_next(ADIR *adir) {  PDIR *dir = (PDIR*) adir;  if(dir−>index < dir−>glob.gl_pathc)   {    ADIRENT *ent = open_std_dirent( dir−>glob.gl_pathv[dir−>index]);    dir−>index++;    return ent;   }  return NULL; } pClose Description Release resources for the directory. Example static void dir_close(ADIR *adir) {  PDIR *dir = (PDIR*) adir;  free(dir−>pPath);  dir−>pPath = NULL;  if(dir−>pFilter)   {    free(dir−>pFilter);    dir−>pFilter = NULL;   }  globfree(dir−>glob); #ifdef_DEBUG  memset(dir, 0, sizeof(PDIR)); #endif/*_DEBUG*/  free(adir); } ADIRENT Interface

See Table 56 for an exemplary ADIRENT API.

TABLE 56 ADIRENT Description This is the abstract directory entry interface. These are returned by ADIR interfaces when enumerating entries in the directory. Prototype struct ADIRENT { text_t *(*pGetFName)(ADIRENT *pEnt); ADIRENT_TYPE (*pGetType)(ADIRENT *pEnt); ADIR *(*pOpenADir)(ADIRENT *pEnt); AFILE *(*pOpenAFile)(ADIRENT *pEnt, AFILE_MODE mode); int (*pRemove)(ADIRENT *pEnt); int (*pRename)(ADIRENT *pEnt1, ADIRENT *pEnt2) int (*pCopy)(ADIRENT *pEnt1, ADIRENT *pEnt2) int (*pStat)(ADIRENT *pEnt, FILESTAT *pFileStat) int (*pSetMode)(ADIRENT *pEnt, faccess_t accessMode) void (*pClose)(ADIRENT *pEnt); }; Example In order to have private data for the ADIRENT, the following data structure is commonly created internally: typedef struct {  ADIRENT adirent;  /*private*/  text_t *fname;  ADIRENT_TYPE type; } PDIRENT; Note that the ADIR implementation references the open_std_dirent( ) function. This allocates memory and initializes the ADIRENT structure. ADIRENT *open_std_dirent(const char *fname) {  PDIRENT *ent;  ent = malloc(sizeof(PDIRENT));  if(ent)   {    ent−>fname = (text_t*) strdup(fname);    ent−>type = ADIRENT_UNKNOWN;    ent−>adirent.pGetFname = dirent_get_fname;    ent−>adirent.pGetType = dirent_get_type;    ent−>adirent.pOpenADir = dirent_open_adir;    ent−>adirent.pOpenAFile = dirent_open_afile;    ent−>adirent.pRemove = dirent_remove;    ent−>adirent.pClose = dirent_close;   }  return (ADIRENT*)ent; } pGetFName Description Returns the name of the file. The actual text_t is system dependant. However, for a given operating system, all ADIRENT implementations must use the same text_t type. Example static text_t *dirent_get_fname(ADIRENT *dirent) {  PDIRENT *ent = (PDIRENT*) dirent;  return ent−>fname; } pGetType Description Returns the type of file. ADIRENT_UNKOWN is returned if an error has occurred. Otherwise, the entry is identified as ADIRENT_AFILE or ADIRENT_ADIR. Use the pOpenADir ( ) and pOpenAFile ( ) functions accordingly. Example static ADIRENT_TYPE dirent_get_type(ADIRENT *dirent) {  PDIRENT *ent = (PDIRENT*) dirent;  struct stat st;  ent−>type = ADIRENT_UNKNOWN;  if(stat((char*)ent−>fname, &st)==0)   {    if(S_ISDIR(st.st_mode))     ent−>type = ADIRENT_ADIR;    else if(S_ISREG(st.st_mode))     ent−>type = ADIRENT_AFILE;   }  return ent−>type; } pOpenADir Description If the entry type is ADIRENT_ADIR, this returns an ADIR for the entry. Example static ADIR *dirent_open_adir(ADIRENT *dirent) {  PDIRENT *ent = (PDIRENT*) dirent;  if(ent−>type != ADIRENT_ADIR)   return NULL;  return open_std_dir((char*)ent−>fname, NULL); } pOpenAFile Description If the entry type is ADIRENT_AFILE, this returns a generic AFILE for the entry. Use OpenADirFilter ( ) and OpenAFileFilter ( ) to access alternate plug-in filters for files. Example static AFILE *dirent_open_afile(ADIRENT *dirent, AFILE_MODE mode) {  PDIRENT *ent = (PDIRENT*) dirent;  if(ent−>type != ADIRENT_AFILE)   return NULL;  return open_std_file((char*)ent−>fname, mode); } pRemove Description Remove the current file entry from the directory. After a call to remove( ), only close( ) may function properly. Example static int dirent_remove(ADIRENT *dirent) {  PDIRENT *ent = (PDIRENT*) dirent;  return unlink((char*)ent−>fname); } pRename Description Renames the pEnt1 to pEnt2. Prototype int (*pRename)(ADIRENT *pEnt1, ADIRENT *pEnt2) pCopy Description Copies directory entry pEnt1 to pEnt2. Prototype int (*pCopy)(ADIRENT *pEnt1, ADIRENT *pEnt2) pStat Description Stat's the given directory entry. Prototype int (*pStat)(ADIRENT *pEnt, FILESTAT *pFileStat) pSetMode Description Changes the read/write file permissions for the directory entry. Prototype int (*pSetMode)(ADIRENT *pEnt, faccess_t accessMode) pClose Description Release resources used by the file entry. Example static void dirent_close(ADIRENT *dirent) {  PDIRENT *ent = (PDIRENT*) dirent;  free(ent−>fname); #ifdef_DEBUG  memset(ent, 0, sizeof(PDIRENT)); #endif  free(ent); } AFILE Interface

See Table 57A for an exemplary AFILE API.

TABLE 57A AFILE Description This is the abstract file interface. These are created by an ADIRENT. Prototype struct AFILE { size_t (*pRead)(AFILE *fp, void *ptr, size_t size); size_t (*pWrite)(AFILE *fp, const void *ptr, size_t size); long (*pTell)(AFILE *fp); long (*pSeek)(AFILE *fp, long offset, int whence); int (*pEof)(AFILE *fp); int (*pError)(AFILE *fp); int (*pSetSize)(AFILE *fp, long offset); int (*pSetMode)(AFILE *fp, AFILE_MODE mode); int (*pClose)(AFILE *fp); }; Example Internally, the following data structure provides extra information for the implementation: typedef struct {  /*public members:*/  AFILE afile;  /*private members:*/  FILE *fp;  char *fname; } PFILE; The open_std_file( ) function is used by ADIRENT to allocate and initialize the AFILE structure. AFILE *open_std_file(const char *fname, AFILE_MODE mode) {  PFILE *file = malloc(sizeof(PFILE));  if(file != NULL)   {    char *file_mode = get_file_mode(mode);    file−>fname = strdup(fname);    file−>fp = fopen(fname, file_mode);    if(file−>fname != NULL && file−>fp != NULL) {   file−>afile.pRead = file_read;   file−>afile.pWrite = file_write;   file−>afile.pSeek = file_seek;   file−>afile.pTell = file_tell;   file−>afile.pClose = file_close;   file−>afile.pEof = file_eof;   file−>afile.pError =file_error;   file−>afile.pSetSize = file_setsize;   return (AFILE*) file; }    if(file−>fname)   free(file−>fname);    if(file−>fp)   fclose(file−>fp);    else   perror(“file error”);    free(file);    file = NULL;   }  return (AFILE*) file; } static char *get_file_mode(AFILE_MODE mode) {  char *file_mode = NULL;  switch(mode)   {   case AFILE_READ_ONLY:    file_mode = “rb”;    break;   case AFILE_WRITE_ONLY:    file_mode = “wb”;    break;   case AFILE_READ_WRITE:    file_mode = “r+b”;    break;   default:    assert(0);    break;   }  return file_mode; } pRead Description Read bytes from the given file. Returns the number of bytes actually read. It may be less than size due to reaching the end of file or an error. Use pEof( ) and pError( ) to detect if at end of the file or whether an error occurred. Example static size_t file_read(AFILE *afile, void *ptr, size_t size) {  PFILE *file = (PFILE*) afile;  return fread(ptr, size, 1, file−>fp); } pWrite Description Write bytes to the given file. Returns the number of bytes actually written. If the return value is less than the number of bytes requested, then an error has occurred. Example static size_t file_write( AFILE *afile, const void *ptr, size_t size) {  PFILE *file = (PFILE*) afile;  return fwrite(ptr, size, 1, file−>fp); } pTell Description Return the current offset into the file. This value can be used with seek( ) to return to the file offset. Prototype long AFILE.tell(AFILE *fp) Example static long file_tell(AFILE *afile) {  PFILE *file = (PFILE *) afile;  return ftell(file−>fp); } pSeek Description Seeks to a new location in the file. Set whence to SEEK_CUR, SEEK_POS, or SEEK_END. Synopsis long AFILE.seek(AFILE *fp, long offset, int whence) Example static int file_seek(AFILE *afile, long offset, int whence) {  PFILE *file = (PFILE*) afile;  return fseek(file−>fp, offset, whence); } pEof Description This returns one if at the end of the file. Otherwise, returns zero. Prototype int AFILE.pEof(AFILE *fp) Example static int file_eof(AFILE *afile) {  PFILE *file = (PFILE*) afile;  return feof(file−>fp); } pError Description This returns zero if no errors have occurred. Otherwise, returns a non-zero value. Example static int file_error(AFILE *afile) {  PFILE *file = (PFILE*) afile;  return ferror(file−>fp); } pSetSize Description Sets the new size of the file. This is intended for truncating the file. pSetMode Description Changes the read/write access mode to the file. pClose Description De-allocates resources used for the file. Example static int file_close(AFILE *afile) {  PFILE *file = (PFILE*) afile;  int ret = fclose(file−>fp);  file−>fp = NULL;  if(file−>fname)   {    free(file−>fname);    file−>fname = NULL;   }  return ret; } Configuration Settings

A configurations settings object manages all configuration settings. This object is use to set and retrieve information in permanent storage. The inner logic of this object manages the way information is stored and accessed. The component manager instantiates this object and passes a configuration settings handle to all other subsystems so they can access their options. Note is that there are no structures involved and each configuration setting is referenced by a symbolic name. As long as the symbolic name is known it can be accessed. Each subsystem uses a prefix to clearly identify its configuration settings.

The following are advantages to this configuration management system, as indicated in Table 57B.

TABLE 57B The logic of how to access information is contained within one object. If the storage method would need to be changed for some reason, it is only one objects implementation that changes and none of the other subsystems get affected. Information is stored in a way that does not allow for user access. If the persistent storage object is not found, default preconfigured values are returned. This way system security is not jeopardized.

Table 57C shows a summary of all configuration settings object interfaces are:

TABLE 57C ScnOptsCreate( ) ScnOptsDestroy( ) ScnOptsGetInt( ) ScnOptsSetInt( ) ScnOptsGetString( ) ScnOptsSetString( )

Following in Table 57D is a detailed description of each API.

TABLE 57D ScnOptsCreate( ) Description The ScnOptsCreate( ) function creates a configuration settings object instance. The handle that is returned by this function call should be passed to all subsequent calls to configuration settings family of functions. Prototype HVSOPTS ScnOptsCreate(void); // Creates configuration settings Parameters No parameters are required. Return Values If NULL value is returned then this function call failed. To find out the reason why this call failed call the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. If the function succeeds it may be a valid handle that should be freed up using the ScnOptsDestroy( ) function when it is not needed anymore. See Also ScnOptsDestroy( ) ScnOptsDestroy( ) Description The ScnOptsDestroy( ) function destroys a configuration settings object instance. The handle passed to it is what was returned from ScnOptsCreate( ) function. Prototype int ScnOptsDestroy( HVSOPTS hOpts ); // Destroys configuration settings Parameters hOpts Handle to a configuration settings object that was obtained from a call to ScnOptsCreate( ). Return Values Zero is returned to indicate success. −1 is returned to indicate error To find out the reason why this call failed called the ErrGet( ) function. This function is thoroughly documented in the platform abstraction layer. See Also ScnOptsCreate( ) ScnOptsGetInt( ) Description The ScnOptsGetInt( ) function retrieves an integer type of value from the configuration settings object. Prototype int ScnOptsGetInt( HVSOPTS   hOpts, // [in] handle to configuration settings text_t * pszSymName, // [in] symbolic name of int value int   * pIntVal // [out] integer value. ); Parameters hOpts Handle to a configuration settings object that was obtained from a call to ScnOptsCreate( ). pszSymName A null terminated symbolic name representing the value that should be retrieved. pIntVal Pointer to an integer value where the requested setting is placed. Return Values Zero is returned to indicate success. Success is that the specified value was found and it was returned in pIntVal. −1 is returned to indicate error. An error is most likely because the value was not found, or the specified symbolic name corresponds to a string type and not to an integer type. See Also ScnOptsSetInt( ), ScnOptsSetString( ), ScnOptsGetString( ) ScnOptsGetString( ) Description The ScnOptsGetString( ) function retrieves an string type of value from the configuration settings object. Prototype int ScnOptsGetString( HVSOPTS   hOpts, // [in] handle to configuration settings text_t * pszSymName, // [in] symbolic name of int value text_t * pCharVal, // [out] string value size_t * pCharLen // [in][out] size of pCharVal on entry. ); Parameters hOpts Handle to a configuration settings object that was obtained from a call to ScnOptsCreate( ). pszSymName A null terminated symbolic name representing the value that should be set. pCharVal Pointer to a string value where the requested configuration setting is placed. pCharLen Upon entry this parameter must contain the maximum number of characters that pCharVal can hold. Upon exit this variable may contain the number of characters placed in this buffer. Return Values Zero is returned to indicate success. Success is that the specified value was found and it was returned in pIntVal. −1 is returned to indicate error. An error is most likely because the value was not found, or the specified symbolic name corresponds to a string type and not to an integer type. See Also ScnOptsSetInt( ), ScnOptsGetInt( ), ScnOptsSetString( ) ScnOptsSetInt( ) Description The ScnOptsSetInt( ) function associates an integer value with the specified symbolic name. Prototype int ScnOptsSetInt( HVSOPTS   hOpts, // [in] handle to configuration settings text_t * pszSymName, // [in] symbolic name of int value int iIntVal // [in] integer value. ); Parameters hOpts Handle to a configuration settings object that was obtained from a call to ScnOptsCreate( ). pszSymName A null terminated symbolic name representing the value that should be set. iIntVal An integer value that is associated with the above symbolic value. Return Values Zero is returned to indicate success. Success is that the specified value was associated with the mentioned symbolic name. −1 is returned to indicate error. See Also ScnOptsGetInt( ), ScnOptsSetString( ), ScnOptsGetString( ) ScnOptsSetString( ) Description The ScnOptsSetString( ) function sets an string type of value to the configuration settings object. Prototype int ScnOptsSetString( HVSOPTS   hOpts, // [in] handle to configuration settings text_t * pszSymName, // [in] symbolic name of int value text_t * pCharVal,   // [in] string value size_t   iCharLen   // [in] size of pCharVal on entry. ); Parameters hOpts Handle to a configuration settings object that was obtained from a call to ScnOptsCreate( ). pszSymName A null terminated symbolic name representing the value that should be retrieved. pCharVal Pointer to a string value that is associated with the above mentioned symbolic name. iCharLen This parameter contains the number of characters in pCharVal to save. Return Values Zero is returned to indicate success. Success is that the specified value was associated with the specified symbolic name. −1 is returned to indicate error. See Also ScnOptsSetInt( ), ScnOptsGetInt( ), ScnOptsGetString( ) Configuration Settings Storage Definition

Configuration settings are stored in a text file in XML format. A sample configuration settings file is described in Table 58.

TABLE 58 < Wireless Settings> <ScanAllFiles=0> <ScanExtensions=SIS,APP,EXE> <LogMaxFileSize=5120> </ Wireless Settings>

ScanAllFiles is the symbolic name for the scan settings that tells whether all files should be scanned or just the files with the specified file extension. Because the value is made up entirely of numbers it should be accessed as a variable type integer.

ScanExtensions is the symbolic name for the scan settings that tells one what file types should be checked for malware in case ScanAllFiles is set to zero. Because the value is made up of alphanumeric values it should be accessed as a string.

Return Codes

The anti-malware scanner core technology architecture returns a common return code. This return code architecture is designed so clear identification can be made between error return codes and simple casual notification return codes. When interfacing with the component manager several other subsystems are involved in protecting the computer systems. From the return code itself it is possible to determine what subsystem is reporting a certain return code and the reason that subsystem decided to report it. This makes problem identification very trivial and notification messages are detailed.

The anti-malware scanner return code is a 32-bit value where each bit position has a meaning. The high order bit, 0x80000000 is set for error return codes only. If this bit is not set then the return code in question corresponds to a notification return code. Each the anti-malware scanner core component has its unique bit position within the return code. Bits positions reserved for subsystem have a range from 0x00100000 to 0x7FF00000 and this allows for detailed debugging and reporting because it is possible to track what subsystems an event traversed through before it was reported. The scanner subsystems use the following bit positions within a return code shown in Table 59.

TABLE 59 VSWSTATUS_SS_CMGR 0x00100000 Component manager VSWSTATUS_SS_OA 0x00200000 On-access scanner VSWSTATUS_SS_OD 0x00400000 On-demand scanner VSWSTATUS_SS_ALOG 0x00800000 Activity log. VSWSTATUS_SS_AGT 0x01000000 Service agent.

This methodology allows for 0xFFFFF possible error codes when combined with the high order bit, and 0xFFFFF notifications when not combined with the high order bit per subsystem.

All return codes that the anti-malware scanner returns can be found in the McStatus.h include file. This include file also contains several helper macros that facilitates return code dissecting. Among these macros are ISSTATUSOK and ISSTATUSERROR that are used for quick determination whether a function call succeeded or not.

More information relating to an illustrative abstract library will be set forth in APPENDIX A.

Back-End Architecture

The back-end architecture provides the following functionality in Table 60.

TABLE 60 Provisioning - Wireless service configuration. Reporting - usage and statistical information from uploaded device information. Communication - device-to-server data communication via HTTP/HTTPS. Database Transaction - device information logging, status update, package selection. Component Update - device-specific component update package preparation and distribution. Server-side scanning (optional) - SMTP, SMS, phone-to- phone information content scanning Architecture

The design goal of the anti-malware scanner back-end infrastructure is to provide a high level of reliability and scalability by distributing the workload to multiple servers. The back-end infrastructure consists of the following components set forth in Table 61

TABLE 61 HTTP server CGI program (kcgi) for client request handling Database transaction server application (pdbserver) for database access. Database for client information storage. Web-based provisioning and reporting system.

With reference again to FIG. 1, client/server communication is initiated by a HTTP POST request from a wireless device to a HTTP server running a CGI named kcgi, an executable invoked by a HTTP daemon to handle client-server communication. Once a HTTP server receives a device request, it connects to a transaction server and sends and receives client-specific data. The transaction server, PDB Server, makes database queries to store and retrieve information to/from a database system. The anti-malware client configuration information, usage information and component update packages are stored in the database. The service configuration and reporting may be accomplished via Web interfaces.

kcgi—HTTP/Web Server CGI

The core CGI engine is implemented through a HTTP/Web server module named kcgi. It has been designed to efficiently handle multiple HTTP requests from wireless devices. The CGI is invoked by a Web server daemon (e.g. Apache) when a wireless device connects and uploads data through an HTTP POST request. See Table 62.

TABLE 62 POST /cgi-bin/kcgi.fcg HTTP/1.0 Host: <BACK-END-HOST> ...

When the CGI receives client data in the payload section of the POST request, it selects a transaction server after a round-robin lookup of a transaction server listing stored in the database and then routes the data to the selected server. Description of the transaction server (pdbserver) and the communication protocol is given in the next section. As a result of the protocol handshaking between kcgi and the pdbserver, a package is either generated or read from a local cache and is sent to the wireless device as PART (data section) of the HTTP response. In case the transaction server returns an error (e.g. authentication failure), kcgi returns an HTTP error response to the HTTP POST request.

PDB Server—Transaction Server Application

The personal device database transaction server, pdbserver, is a server application designed to be situated in-between a HTTP/Web server running kcgi and a database server(s) containing device and vendor-specific status and information. The pdbserver is a single-threaded, single-process application designed to handle multiple connections.

Command Line Arguments

The pdbserver supports six command line arguments—IP number, process user id, log directory path, upload package directory path, server listener port number, and maximum client connection.

Table 63 illustrates an example.

TABLE 63 ./pdbserver --ip 161.69.79.100 --user pdbd --pkg /pdbd/packages --port 6179 --max-clients 256

The example command line instructs pdbserver to register with a database as a server with IP “161.69.79.100”, execute as a user “pdb” process, find packages in the “/pdbd/packages” directory, listens to connections on port 6179 and allow up-to 256 simultaneous client connections at a give time.

By default pdbserver saves posted log files under the “./”+<ip>+“:”+<port> directory. For the above example, pdbserver saves posted log files into the “./161.69.79.100:6179” directory. See Table 64 for exemplary pdbserver command-line arguments.

TABLE 64 Argument Req'd Default Example Description --ip ✓ none 161.69.79.100 This is the IP address of the pdbserver saved to the database. The pdbserver binds to all interfaces of the system it is running on. --port 6179 6188 Server port number. --user ✓ none pdbd pdbserver process user-id --log <IP>:<PORT> ./161.69.79.100:617 Where to save posted log 9 data --pkg ✓ none /pdbd/packages Where to locate packages to be downloaded to clients. --max- 64 256 Maximum number clients. clients Architecture

The pdbserver is a single-process, single-threaded server application designed to serve multiple client connections simultaneously. Communication with clients is done using custom protocol over TCP/IP. The application code consists of three parts: initialization, service loop and cleanup.

Initialization

The initialization code consists of three parts: database connection/login, registration, and network/socket initialization.

Database Login

The current pdbserver implementation uses an Oracle user id “mdb”, password “tigard”, and connection string “lara” to log onto a remote PDB server. The Oracle connection string “lara” is used to reference a remote Oracle database server and must be defined in Oracle client network configuration file tnsnames.ora. Table 65 illustrates an example tnsnamees.ora for an Oracle server running on the computer at pdb00.dev.mcafeelabs.com listening to port 1521. See Table 65 for an exemplary sample tnsnames.ora configuration.

TABLE 65 LARA.DEV.MCAFEELABS.COM = (DESCRIPTION = (ADDRESS LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = pdb00.dev.mcafeelabs.com)(PORT = 1521)) ) (CONNECT_DATA = (SERVICE_NAME = pdb00.dev.mcafeelabs.com) ) ) Registration

Once a database connection is established, the pdbserver registers itself with the database. The back-end database keeps a list of pdbserver information for load-balancing purpose. The stored information can be obtained by a kcgi instance using the query-servers command.

Socket Initialization

The server's listener socket is initialized with no-delay mode, and the listener port is set to a user specified port number. The reason for setting the server socket in no-delay mode is to service clients without having to wait for read/write completion.

Service Loop

The pdbserver's main loop consists of accepting a connection to the listener socket, polling each client connection for I/O status updates, servicing each client's request, and removing clients who have timed out. The client network I/O status (read-ready, write-ready, error condition) is obtained using the poll API function. After each client's I/O status is updated, the server handles I/O requests for those clients whose I/O status is set for read/write and executes clients' commands when they are ready to execute.

Protocol

The kcgi/pdbserver communication protocol consists of a command and response sets. Each command/response is made up of a minimum of 8 bytes—the first 4 bytes for command/response code and the next 4 bytes for command/response data length. The command/response code and data length information are encoded in network-byte order. Command/response data is given if the length specified is not zero. See Table 66 for an exemplary command/response format.

TABLE 66 <command/response:4 bytes> <data-length:4 bytes> [data:data-length bytes]

FIG. 20 illustrates a transaction server command process flow 2000, in accordance with one embodiment. As shown, a command is received in operation 2002, after which it is identified as a post data command 2004, a query server command 2006, or a quit command 2008. If the command received is a post data command 2004, device information is updated in operation 2010, an update package is retrieved in operation 2012, a log is saved in operation 2014, and the response is sent in operation 2020. Further, if the command received is a query server command 2006, a server list is retrieved in operation 2016, and the response is sent in operation 2020. Further, the quit command 2008 prompts a bye operation. See operation 2018. More information regarding such commands will now be set forth.

Commands

The pdbserver accepts three commands from kcgi: post-data, query-servers and quit. Each command consists of a 4-byte command code followed by a 4-byte command argument length and data. See Table 67 for an exemplary PDB Server Command List.

TABLE 67 Command Value Description post-data 0x0001 Uploads device log file. query-servers 0x0002 retrieves the file version number of the latest device-specific virus signature file stored in database. quit 0x0004 ends client connection to the pdbserver. Post-data

One of the main functionalities of the pdbserver is to verify and update individual device's status on the back-end database. The post-data command is used by kcgi to upload (or post) data sent by a wireless device using HTTP POST. Contained in the uploaded client data is a wireless component catalogue containing version information and event log. The catalogue information is used in selecting an update package to download to the device, and the log data is stored in the database for reporting. At the very beginning of the HTTP POST data is a device identification number used to authenticate the device. Both the catalogue and the log information received are in XML format. Refer to the service agent section of the anti-malware scanner Design Specification document for the catalogue and event log format.

Query-servers

This command is used by kcgi in selecting a pdbserver, and returns a list of active PDB server IP's, port assignment, and number of clients connected to each server.

Return Code

For each command issued by a client, the pdbserver responds with a 4-byte response code followed by a 4-byte data length. Table 68A lists the current pdbserver response codes.

TABLE 68A Response Value Description success 0x0000 command executed successfully. cmd-failed 0x8001 failed to execute command unknown-cmd 0x8002 unknown command issued invalid-arg 0x8003 invalid command argument given timeout 0x8004 client failed to issue command on time not-impl 0x8005 issued command not implemented invalid-data 0x8006 same as invalid-arg; client data contains invalid argument data no-record 0x8007 failed to locate requested (or required) data from database db-failure 0x8008 database transaction failure db-unavail 0x8009 failed to connect to database insuf-res 0xCFFE insufficient internal resource to execute requested command internal-err 0xCFFF unknown internal error Configuration and Reporting

The anti-malware scanner run-time configuration is setup through a web interface and maintained in the database. New configuration settings in XML format are downloaded to each device as a part of the HTTP POST return data. Each device entry in the unit information table has a group id used to reference the configuration for a given wireless device. Currently identified configuration settings are those set forth in Table 68B.

TABLE 68B Service-interval time - how often wireless devices contact the back-end to upload/download data from the back-end Scan action - virus scanner action (clean/repair, delete, ignore)

Usage and statistical reports are generated using a Web interface from database records gathered from device logs uploaded by the service agent on the device. Two types of reports are available, as indicated by Table 68C.

TABLE 68C Virus detection reports - statistical information on the virus names, types, actions taken. System activity reports - compilation of system errors and warnings used to diagnose and troubleshoot. Database Schema

FIG. 21 illustrates the personal device database table relationships 2100, in accordance with one embodiment. The personal device database (PDB) is a relational database made up of six tables: unit_info (2102), device (2104), eng_pkg (2106), dat_pkg (2108), detection_log (2110), event_log (2112) and pdbserver (2114). The information contained in the relational database tables are used by a pdbserver to retrieve individual devices' engine and PD information, detection and event log records, and to list available pdbserver's for kcgi.

Device Information Table (2104 of FIG. 21)

Device-specific latest engine and DAT version information is kept in the device table. See Table 69 for an exemplary device information table.

TABLE 69 device column type key example description id varchar(16) ✓ MOT10A device identification number engver varchar(10) EM10A.5.2.1 latest AV engine version number for the device ‘id’ datver varchar(10) DM10A.5.2.1 latest AV signature database version for the device ‘id’ mfg varchar(32) Motorola device manufacture name rev varchar(16) A device revision number cmnt varchar(128) Motorola Model 10 A device comment/remark text for Verizon Engine Package Table (2106 of FIG. 21)

Engine package filename for a specific device type and version is stored in the eng_pkg table. See Table 70 for exemplary device-specific engine package information.

TABLE 70 eng_pkg column type key example description device varchar(16) ✓ M0T10A device identification number version varchar(10) ✓ EM10A.5.2.0 latest AV engine version number for the device pkg varchar(64) eng.m10a.050200.pkg AV engine package name DAT Package Table (2108 of FIG. 21)

The DAT package table (dat_pkg) contains device and version specific DAT package name information. See Table 71 for exemplary device-specific DAT package information.

TABLE 71 dat_pkg column type key example desription device varchar(16) ✓ M0T10A device identification number version varchar(10) ✓ EM10A.5.2.0 latest AV signature database version number for the device pkg varchar(64) dat.m10a.5.2.0.pkg signature package name Unit Information Table (2102 of FIG. 21)

Every personal device has an entry in the unit_info table. Stored in this table are: 16-character fixed-length unit identification number, device identification number that specifies the device type, unit-group identification code that provides group association of a particular unit and virus scan data files and engine version numbers on the device. See Table 72 for an exemplary unit information table.

TABLE 72 unit_info column type key example description unitid char(16) ✓ C000A100008001234 personal device unit identification number deviceid varchar(16) M0T10A device identification number group char(8) VZ200 unit group identification number status int 1 unit activation status engver varchar(10) EM10A.5.2.1 AV engine version on the unit datver varchar(10) DM10A.5.2.1 AV signature version on the unit contact char(14) 20011224161525 last log upload timestamp (UTC); YYYY + MM + DD + hh + mm + ss Detection Log (2110 of FIG. 21)

Virus/malware detection log entries posted by a device are kept in the detection log. Each log entry has unit identification number, timestamp, what was detected, and action taken by the scanner. See Table 73 for an exemplary malware detection log table.

TABLE 73 detection_log column type key example description unitid char(16) C000A100008001234 personal device unit identification number when char(14) 20011224161030 reported detection timestamp (UTC) detected varchar(32) abc@mm malware name type varchar(16) worm malware type infected varchar(128) system.dll object (e.g. file) infected action int 1 AV scanner action Event Log (2112 of FIG. 21)

System log information upload by devices are kept in the event log. Each log entry consists of unit id, log entry time, severity of the event, and event description. See Table 74A for an exemplary event log table.

TABLE 74A event_log column type key example description unitid char(16) C000A100008001234 personal device unit identification number when char(14) 20011224161025 reported detection timestamp (UTC) severity int 1 severity-level of the reported event message varchar(160) DAT updated event description successfully PDB Server Table (2114 of FIG. 21)

PDB server table lists active pdbserver instances and the number of clients each server is servicing. As a part of initialization process, each pdbserver registers its IP and port to the table, and maintains a client counter in the table. See Table 74B.

TABLE 74B pdbserver column type key description ip varchar(15) ✓ PDB Server IP number port int ✓ PDB server port number clients int number of clients being served by IP:port PDB Logger

The PDB Logger (pdblogger) is a separate application designed to process posted device log data as an off-line process. The system event and detection log information stored in a log directory is processed and recorded onto the event and detection tables by this application.

FIG. 22 shows an exemplary client information flow 2200, in accordance with one embodiment.

APPENDIX A

Abstract Library

The design goal of the wireless abstraction library is to shield the application from platform-specific implementation details while providing consistent interfaces to the following subsystems in Table 75.

TABLE 75 dynamic memory allocation process enumeration and control threading and thread synchronization storage I/O network socket I/O string conversion system event handling Initialization

An application using the API Library is required to make a call to the AlInitLibrary function before calling any other API functions. Also the user application is required to call the AlCleanupLibrary before terminating to release any system resources internal to the library. See Table 76.

TABLE 76 Initialization API Name Arguments Returns Description AlInitLibrary void int initialize library AlCleanupLibrary void int release system resource used Error Functions

The abstraction library provides two functions to set and retrieve the last-error code for the calling thread. See Table 78.

TABLE 78 Error API Name Arguments Returns Description AlErrGetLast void AlErrorCode retrieves last-error code AlErrSetLast AlErrorCode void sets the last-error code System Information API

See Table 79.

TABLE 79 Child Process API Name Arguments Returns Description AlGetDeviceID text_t* pId, int retrieves the system int iSize identification string Process API

The abstraction library provides a set of functions for a child process execution, process list enumeration and process termination.

See Table 80.

TABLE 80 Process API Name Arguments Returns Description AlExec text_t const* int loads and executes a new process pProg, text_t const* pCmdLine AlProGetList AlPID* pPIDs, int retrieves system process list int iMaxPIDs AlProFreeList AlPID* pPIDs, int releases memory used to store int iPIDs process list AlProOpen AlPID pid AL_PROCESS_HANDLE converts process id to process handle AlProClose AL_PROCESS_HANDLE int release process handle returned by hProcess the AlProOpen function AlProKill AL_PROCESS_HANDLE int force terminates a given process hProcess Dynamic Memory API

The abstraction library provides two sets of dynamic memory allocation methods for multi-threaded applications. Under operating systems like Unix/Linux and Windows NT (Win32), a block of memory allocated from one thread using the malloc( ) function can be de-allocated in another thread, but under systems like Symbian 6.x, memory de-allocation must be performed by the thread that created it. The AlMemSAlloc and AlMemSFree functions are provided to allocate/deallocate dynamic memory from the process thread, and the AlMemAlloc and the AlMemFree functions are provided for thread-specific memory allocation/de-allocation. Under Unix/Linux and Win32, both AlMemSAlloc and AlMemAlloc are mapped to the POSIX malloc. See Table 81.

TABLE 81 Dynamic Memory API Name Arguments Returns Description AlMemSAlloc unsigned int uSize void* allocate memory from the parent thread's heap AlMemSFree void* ptr void free memory allocated using the AlMemSAlloc function. AlMemAlloc unsigned int uSize void* allocate memory from the calling thread's heap AlMemFree void* ptr void free memory allocated using the AlMemAlloc function. Thread API

The library provides thread creation and termination functions. The AlCreateThread creates a new thread, the AlWaitThread provides thread termination waiting function, and the AlCloseThread is used to release system resource associated with a thread.

See Table 83.

TABLE 83 Thread API Name Arguments Returns Description AlCreateThread int AL_THREAD_HANDLE create a new thread (*pThreadProc) (void*), void *pData, int iStackSize = −1, int iMinHeap = −1, int iMaxHeap = −1 AlWaitThread AL_THREAD_HANDLE int wait for thread to hThread, terminate int iMsTimeout AlCloseThread AL_THREAD_HANDLE void close and release thread hThread resource AlGetTls void void* returns the pointer thread-local storage AlSetTls void void* sets the pointer thread- local storage AlSleep int int suspends the calling thread Synchronization API

The abstraction library provides three types of thread synchronization objects: mutex, semaphore and critical section. Both unnamed and named mutex and semaphore objects are supported. See Table 84.

TABLE 84 Synchronization API Name Arguments Returns Description AlCreateMutex text_t const *pName AL_MUTEX_HANDLE create a new mutex AlOpenMutex text_t const *pName AL_MUTEX_HANDLE get handle to an existing mutex AlGetMutex AL_MUTEX_HANDLE int lock a given mutex hMutex AlReleaseMutex AL_MUTEX_HANDLE int unlock a given mutex hMutex AlCloseMutex AL_MUTEX_HANDLE void close and release mutex hMutex resource AlCreateSemaphore text_t const AL_SEMAPHORE_HANDLE create a new semaphore *pName, int iCount AlOpenSemaphore text_t const *pName AL_SEMAPHORE_HANDLE open an existing semaphore AlGetSemaphore AL_SEMAPHORE_HANDLE int wait on the specified hSemaphore semaphore AlReleaseSemaphore AL_SEMAPHORE_HANDLE int increase the count of the hSemaphore, specified semaphore by a int iCount given amount AlCloseSemaphore AL_SEMAPHORE_HANDLE void close and release hSemaphore, semaphore int iCount AlCreateCritsec void AL_CRITSEC_HANDLE create a critical section AlGetCritsec AL_CRITSEC_HANDLE int wait for ownership of a hCritsec specified critical section AlReleaseCritsec AL_CRITSEC_HANDLE int release the ownership of hCritsec a critical section AlCloseCritsec AL_CRITSEC_HANDLE void close and release the hCritsec specified critical section and its resource Storage I/O

The Storage I/O API is used by the anti-malware scanner to access and modify data objects (or files) stored on a non-volatile storage device (e.g. flash memory, hard disk) and managed by a file system or file system like storage and retrieval system. The API is divided into three categories: 1) I/O routines for reading/writing data to/from single object or file, 2) calls used to copy, move and delete a stored object, 3) and routines that provide directory object enumeration. See Table 85.

TABLE 85 Storage I/O API Name Arguments Returns Descriptions AlFsFileOpen text_t const AL_FILE_HANDLE open a file for reading/writing and *pFName, returns file handle unsigned int uMode AlFsFileClose AL_FILE_HANDLE int release and close file handle hFile AlFsFileRead AL_FIL_HANDLE int read file data hFile, unsigned char* buffer, int nSize AlFsFileWrite AL_FIL_HANDLE int write data to file hFile, unsigned char const* buffer, int iSize AlFsFileSeek AL_FIL_HANDLE long reposition read/write file offset hFile, long offset, int iWhence AlFsFileTell AL_FIL_HANDLE long obtain read/write file offset hFile AlFsFileSetSize AL_FIL_HANDLE long change file size hFile, long lNewSize AlFsFileDelete text_t const* int delete file pFName AlFsFileRename text_t const* int rename a file or directory pOFName, text_t const* pNFName); AlFsFileCopy text_t const* int copy a file pSFName, text_t const* pSFName AlFsFileStat text_t const* int obtain a file or directory pFName, struct information AlFileStat* pFStat AlSetFileMode text_t const* int set a file or directory attribute pFName, unsigned long ulMode AlFsBuildPath text_t const* text_t* construct a path from directory and pDName, text_t file paths const* pFName AlFsGetRoots text_t int obtain a lists of roots. **pRoots, int iMaxRoots AlFsDirOpen text_t const AL_DIR_HANDLE open a directory *pDName AlFsDirClose AL_DIR_HANDLE int close directory handle hDir AlFsDirNext AL_DIR_HANDLE int obtain a directory entry hDir, struct AlDirEntry* pDE AlFsIsDir AlFAtt attrib int test for directory AlFsGetTemp text_t* const text_t* returns a full path for a temporary pDirectory file Network Sockets API

Both standard and secure (SSL) socket API's for developing client/server applications are provided in the abstraction library. See Table 86.

TABLE 86 Socket API Name Arguments Returns Description AlSockCreate int iDomain, AL_SOCKET_HANDLE creates and returns a int iType, handle to a socket int iProtocol object AlSockClose AL_SOCKET_HANDLE int closes a socket handle hSock AlSockBind AL_SOCKET_HANDLE int binds a network address hSock, to a socket AlSockAddr *pAddr AlSockAccept AL_SOCKET_HANDLE int accepts a connection to hSock, a socket int iMsTimeout AlSockConnect AL_SOCKET_HANDLE int establishes a connection hSock, to a peer AlSockAddr *pAddr, int iMsTimeout AlSockRecv AL_SOCKET_HANDLE int receives data from a hSock, socket connection unsigned char *Buffer, int iSize, int iMsTimeout AlSockSend AL_SOCKET_HANDLE int sends data on a hSock, connected socket unsigned char const *Buffer, int iSize, int iMsTimeout AlSockAddrBuild text_t const *pHName, int converts a hostname and int iPort, port into a socket AlSockAddr *pAddr address

See Table 87 for a secure socket API.

TABLE 87 Secure Socket API Name Arguments Returns Description AlSSockOpen AL_SOCKET_HANDLE int converts non-secure hSock socket into a secure socket object for SSL communication AlSSockClose AL_SSOCKET_HANDLE int closes SSL socket hSSock AlSSockBind AL_SSOCKET_HANDLE int SSL version of hSSock, AlSockBind AlSockAddr *pAddr AlSSockAccept AL_SSOCKET_HANDLE int SSL version of hSSock, AlSockAccept int iMsTimeout AlSSockConnect AL_SSOCKET_HANDLE int SSL version of hSSock, AlSockConnect AlSockAddr *pAddr, int iMsTimeout AlSSockRecv AL_SSOCKET_HANDLE int SSL version of hSSock, AlSockRecev unsigned char *Buffer, int iSize, int iMsTimeout AlSSockSend AL_SSOCKET_HANDLE int SSL version of hSSock, AlSockSend unsigned char const *Buffer, int iSize, int iMsTimeout String Functions

The string functions in the Platform Abstraction Library provide a platform-specific string type to/from an UTF8 string conversions and string type-specific allocation functions. See Table 88.

TABLE 88 String API Name Arguments Returns Description AlStrCpyFromTStr char* pDest, char* copy and convert text_t const* pSrc platform-specific string type to an UTF8 string AlTStrCpyFromStr text_t* pDest, text_t* copy and convert a char const* pSrc UTF8 string to a platform-specific string AlStrAlloc unsigned int uSize char* create a buffer for a single-byte zero- terminated string AlStrDup char const* pStr char* duplicate given single- byte zero-terminated string AlStrTrans text_t const* pTStr char* convert a platform- specific string to an UTF8 string AlStrFree char* pStr void release memory allocated by the AlStrAlloc, AlStrDup and AlStrTrans functions AlStrIStr char const* pString, char* locate ‘pPattern’ char const* pPattern in ‘pString’ and return a pointer the beginning of the found string AlTStrAlloc unsigned int uSize text_t* allocate and return a pointer to a buffer large enough to hold ‘uSize’ long text_t string AlTStrDup text_t const* pString text_t* duplicate a platform- specific string and return a pointer to the duplicated string AlTStrTrans char const* pString text_t* convert an UTF8 string to a platform-specific string AlTStrFree text_t* pString void release memory allocated to hold a text_t string by the AlTStrAlloc, AlStrDup and the AlTStrTrans functions AlTStrLen text_t* pString int return length of a platform-specific string System Event Functions

The system event functions provides an application with a method to install an event handler for a given system event. See Table 89.

TABLE 89 System Event API Name Arguments Returns Description AlEventGetHandler int event, int obtain existing event AL_EVENT_CBFUNC* handler for specified pCbFunc event AlEventSetHandler int event, int set a callback handler AL_EVENT_CBFUNC for specified event cbFunc API Reference

See Table 90 for an exemplary API reference.

While various embodiments have been described above, it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of a preferred embodiment should not be limited by any of the above described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents. 

1. A method for scanning a mobile wireless device for malware, comprising: calling a platform abstraction layer of a mobile wireless device; accessing data stored in persistent memory of the mobile wireless device; and initiating an anti-malware scanner-related function module on the mobile wireless device to scan the data utilizing the platform abstraction layer; wherein the platform abstraction layer enables the anti-malware scanner-related function module to be initiated on any of a plurality of different mobile wireless devices; wherein the data is accessed utilizing an abstract file system interface; wherein the abstract file system interface is implemented for each class of the data stored in the persistent memory.
 2. The method as recited in claim 1, wherein the platform abstraction layer includes storage I/O interfaces.
 3. The method as recited in claim 1, wherein the platform abstraction layer includes dynamic memory allocation interfaces.
 4. The method as recited in claim 1, wherein the platform abstraction layer includes process control call interfaces.
 5. The method as recited in claim 1, wherein the platform abstraction layer includes network I/O call interfaces.
 6. The method as recited in claim 1, wherein the platform abstraction layer includes system event handler interfaces.
 7. The method as recited in claim 1, wherein the platform abstraction layer includes system information routine interfaces.
 8. The method as recited in claim 1, wherein the platform abstraction layer includes storage I/O interfaces, dynamic memory allocation interfaces, process control call interfaces, network I/O call interfaces, system event handler interfaces, and system information routine interfaces.
 9. The method as recited in claim 1, wherein the platform abstraction layer provides a common view of an operating system of the mobile wireless device.
 10. The method as recited in claim 1, wherein the abstract file system interface includes an abstract directory interface.
 11. The method as recited in claim 1, wherein the abstract file system interface includes data structures with call back functions.
 12. The method as recited in claim 11, wherein the call back functions enumerate the data.
 13. The method as recited in claim 11, wherein the call back functions manipulate the data.
 14. A computer program product for scanning a mobile wireless device for malware, comprising: computer code for calling a platform abstraction layer of a mobile wireless device; computer code for accessing data stored in persistent memory of the mobile wireless device; and computer code for initiating an anti-malware scanner-related function module on the mobile wireless device to scan the data utilizing the platform abstraction layer; wherein the platform abstraction layer enables the anti-malware scanner-related function module to be initiated on any of a plurality of different mobile wireless devices; wherein the data is accessed utilizing an abstract file system interface; wherein the abstract file system interface is implemented for each class of the data stored in the persistent memory.
 15. The computer program product as recited in claim 14, wherein the platform abstraction layer includes storage I/O interfaces.
 16. The computer program product as recited in claim 14, wherein the platform abstraction layer includes dynamic memory allocation interfaces.
 17. The computer program product as recited in claim 14, wherein the platform abstraction layer includes process control calls.
 18. The computer program product as recited in claim 14, wherein the platform abstraction layer includes network I/O calls.
 19. The computer program product as recited in claim 14, wherein the platform abstraction layer includes system event handler interfaces.
 20. The computer program product as recited in claim 14, wherein the platform abstraction layer includes system information routines.
 21. The computer program product as recited in claim 14, wherein the platform abstraction layer includes storage I/O interfaces, dynamic memory allocation interfaces, process control calls, network I/O calls, system event handler interfaces, and system information routines.
 22. The computer program product as recited in claim 14, wherein the platform abstraction layer provides a common view of an operating system of the mobile wireless device.
 23. A system for scanning a mobile wireless device for malware, comprising: logic for calling a platform abstraction layer of a mobile wireless device; logic for accessing data stored in persistent memory of the mobile wireless device; and logic for initiating an anti-malware scanner-related function module on the mobile wireless device to scan the data utilizing the platform abstraction layer; wherein the platform abstraction layer enables the anti-malware scanner-related function module to be initiated on any of a plurality of different mobile wireless devices; wherein the data is accessed utilizing an abstract file system interface; wherein the abstract file system interface is implemented for each class of the data stored in the persistent memory.
 24. A system for scanning a mobile wireless device for malware, comprising: means for calling a platform abstraction layer of a mobile wireless device; means for accessing data stored in persistent memory of the mobile wireless device; and means for initiating an anti-malware scanner-related function module on the mobile wireless device to scan the data utilizing the platform abstraction layer; wherein the platform abstraction layer enables the anti-malware scanner-related function module to be initiated on any of a plurality of different mobile wireless devices; wherein the data is accessed utilizing an abstract file system interface; wherein the abstract file system interface is implemented for each class of the data stored in the persistent memory.
 25. A method for scanning a mobile wireless device for malware, comprising: calling a platform abstraction layer of a mobile wireless device; accessing data stared in persistent memory of the mobile wireless device; and initiating an anti-malware scanner-related function module on the mobile wireless device to scan the data utilizing the platform abstraction layer; wherein the platform abstraction layer includes entities selected from the group consisting of storage I/O interfaces, dynamic memory allocation interfaces, process control call interfaces, network I/O call interfaces, system event handler interfaces, and system information routine interfaces; wherein the data is accessed utilizing an abstract file system interface; wherein the abstract file system interface is implemented for each class of the data stored in the insistent memory. 